How many questions from Redox Reactions and Electrochemistry appear in JEE?

Redox Reactions and Electrochemistry has appeared in 177 of the last 186 JEE Main and JEE Advanced papers — about 95% of them — contributing 265 questions in total across those papers.

Is Redox Reactions and Electrochemistry an important chapter for JEE?

Judged by how often it is actually tested, it appears in roughly 95% of papers. Chapters above about 50% are effectively guaranteed to show up every session, so they repay thorough preparation; lower-frequency chapters are better treated as targeted revision.

Where do these Redox Reactions and Electrochemistry questions come from?

Every question is from an official JEE Main or JEE Advanced paper, transcribed from the original paper and tagged to this chapter. Answers follow the official answer key.

Redox Reactions and Electrochemistry JEE Previous Year Questions with Answers

Q1·ChemistrySingle correctJEE Advanced 2026

At 300 K, the molar conductivities of the aqueous solutions of three salts at two different concentrations are given below: The conductivity of a saturated aqueous solution of AgCl is

1.40 \times 10^{-6}

S

cm^{-1}

at 300 K. If the solubility of AgCl in water at 300 K is

X

mol

L^{-1}

, then

\log_{10}(X^{-1})

is (Assume that AgCl dissolved in water ionizes completely and that the molar conductivity of saturated AgCl solution is equal to its limiting molar conductivity.)

Salt	Concentration (M)	Molar conductivity (S cm $^{2}$ mol $^{-1}$ )
$NaNO_{3}$	0.01	111
$NaNO_{3}$	0.04	101
$NaCl$	0.01	117
$NaCl$	0.04	107
$AgNO_{3}$	0.01	125
$AgNO_{3}$	0.04	116

(A)3
(B)4
(C)5
(D)6

Q2·ChemistrySingle correctJEE Main 2026

Given at 298 K:

E^{\ominus}_{Fe^{2+}/Fe} = X

Volt;

E^{\ominus}_{Fe^{3+}/Fe} = Y

Volt. The

E^{\ominus}_{Fe^{3+}/Fe^{2+}}

in Volt at 298 K is given by:

(A) $2X - 3Y$
(B) $3Y - 2X$
(C) $3Y + 2X$
(D) $Y + X$

Q3·ChemistrySingle correctJEE Main 2026

Consider the following data. BaSO₄ is sparingly soluble in water. If the conductivity of the saturated BaSO₄ solution is x S cm⁻¹ then the solubility product of BaSO₄ can be given as (Here Λm = Λ°m)

Electrolyte	Λ°m (S cm² mol⁻¹)
BaCl₂	x₁
H₂SO₄	x₂
HCl	x₃

(A) $\frac{10^{6}x^{2}}{\alpha^{2}(x_1 + x_2 - 2x_3)^{2}}$
(B) $\frac{x^{2}}{(x_1 + x_2 - 2x_3)^{2}}$
(C) $\frac{\alpha^{2}(x_1 + x_2 - 2x_3)^{2}}{10^{6}x^{2}}$
(D) $\frac{x^{2}}{(x_1 + x_2 + 2x_3)^{2}}$

Q4·ChemistryNumericalJEE Main 2026

500 mL of 0.2 M

\mathrm{MnO_{4}^{-}}

solution in basic medium when mixed with 500 mL of 1.5 M KI solution, oxidises iodide ions to liberate molecular iodine. This liberated iodine is then titrated with a standard

x

M thiosulphate solution in presence of starch till the end point. If 300 mL of thiosulphate was consumed, then the value of

x

is __________.

Q5·ChemistrySingle correctJEE Main 2026

For a general redox reaction Anode :

\mathrm{Red_{1}} \rightarrow \mathrm{Ox_{1}^{n_{1}^{+}}} + n_{1}e^{-}

Cathode :

\mathrm{Ox_{2}} + n_{2}e^{-} \rightarrow \mathrm{Red_{2}^{n_{2}^{-}}}

Which of the following statement is incorrect ?

(A)The overall reaction can be written as $n_{2}\mathrm{Red_{1}} + n_{1}\mathrm{Ox_{2}} \rightleftharpoons n_{2}\mathrm{Ox_{1}^{n_{1}^{+}}} + n_{1}\mathrm{Red_{2}^{n_{2}^{-}}}$
(B)The electrons do not appear in the overall reaction because electrons produced at the anode are consumed at the cathode.
(C)Here $n$ is the number of electrons transferred in redox reaction.
(D)If the reaction is carried out reversibly, the electrical work done is equal to the ratio of charge and potential difference through which charge is moved.

Q6·ChemistryNumericalJEE Main 2026

At 298 K, the molar conductivity of x% (w/w) MX solution (aqueous) is 123.5 S cm² mol⁻¹. The conductance of same solution is 1.9 × 10⁻³ S. The value of x is _______ ×10⁻². (Given : cell constant = 1.3 cm⁻¹; molar mass of MX is 75 g mol⁻¹, density of aqueous solution of MX at 298 K is 1.0 g mL⁻¹)

Q7·ChemistrySingle correctJEE Main 2026

One half cell in a voltaic cell is constructed by dipping silver rod in AgNO₃ solution of unknown concentration, other half cell is Zn rod dipped in 1 molar solution of ZnSO₄. A voltage of 1.60 V is measured at 298 K for this cell. What is the concentration of Ag⁺ ions used in terms of log x (x = [Ag⁺]) ?

E^{\circ}_{Zn^{2+}/Zn}

= −0.76 V,

E^{\circ}_{Ag^{+}/Ag}

= +0.80 V,

\frac{2.303RT}{F}

= 0.059 V

(A) $\frac{2}{3.9}$
(B) $\frac{4}{5.9}$
(C) $\frac{2.9}{2}$
(D) $\frac{5.9}{4}$

Q8·ChemistryNumericalJEE Main 2026

An electrochemical cell, consist of the following two redox couples,

M^{x+}(aq)/M(s)

[E^{\ominus}_{red}

= +0.15 V] and

\mathrm{Fe^{3+}}(aq)/\mathrm{Fe}(s)

[E^{\ominus}_{red}

= −0.036 V]. The cell EMF (

E_{cell}

) is recorded to be 0.2057 V. If the reaction quotient of the electrochemical reaction is found to be 10

^{-2}

, then the value of

x

is ______. (Nearest integer) [Given: M is a p-block metal and

\frac{2.303RT}{F}

= 0.059 V]

Q9·ChemistrySingle correctJEE Main 2026

In order to oxidise a mixture of 1 mole each of

FeC_2O_4

,

Fe_2(C_2O_4)_3

,

FeSO_4

and

Fe_2(SO_4)_3

in acidic medium, the number of moles of

KMnO_4

required is

(A)3
(B)2
(C)5
(D)7

Q10·ChemistrySingle correctJEE Main 2026

An electrochemical cell is constructed using half cells in the direction of spontaneous change

\mathrm{Fe(OH)_{2}}(s) + 2e^{-} \rightarrow \mathrm{Fe}(s) + 2\mathrm{OH^{-}}(aq)

E^{\theta} = -0.88

V and

\mathrm{AgBr}(s) + e^{-} \rightarrow \mathrm{Ag}(s) + \mathrm{Br^{-}}(aq)

E^{\theta} = +0.07

V Which of the following option is correct?

(A)Overall reaction $\mathrm{Fe}(s) + 2\mathrm{OH^{-}}(aq) + 2\mathrm{AgBr}(s) \rightleftharpoons \mathrm{Fe(OH)_{2}}(s) + 2\mathrm{Ag}(s) + 2\mathrm{Br^{-}}(aq)$
(B) $E^{\theta}_{cell} = -0.95$ V
(C)Fe is reduced in the electrochemical cell
(D) $E^{\theta}_{cell}$ is an extensive property

Q11·ChemistryNumericalJEE Main 2026

Consider the following two half-cell reactions along with the standard reduction potential given:

CO_2 + 6H^+ + 6e^- \rightarrow CH_3OH + H_2O

E^\circ_{red} = 0.02

V

\frac{1}{2}O_2 + 2H^+ + 2e^- \rightarrow H_2O

E^\circ_{red} = 1.23

V A fuel cell was set up using the above two reactions such that the cell operates under the standard condition of 1 bar pressure and 298 K temperature. The fuel cell works with 80% efficiency. If the work derived from the cell using 1 mol of

CH_3OH

is used to compress an ideal gas isothermally against a constant pressure of 1 kPa, then the change in the volume of the gas,

\Delta V =

______ m

^3

. (nearest integer) Given:

F = 96500

C mol

^{-1}

Q12·ChemistryNumericalJEE Main 2026

500 mL of 1.2 M KI solution is mixed with 500 mL of 0.2 M KMnO

_{4}

solution in basic medium. The liberated iodine was titrated with standard 0.1 M Na

_{2}

S

_{2}

O

_{3}

solution in the presence of starch indicator till the blue color disappeared. The volume (in L) of Na

_{2}

S

_{2}

O

_{3}

consumed is________. (Nearest integer)

Q13·ChemistryNumericalJEE Main 2026

Consider the following redox reaction taking place in acidic medium BH

_{4}^{-}

(aq)

+

ClO

_{3}^{-}

(aq)

\rightarrow

H

_{2}

BO

_{3}^{-}

(aq)

+

Cl

^{-}

(aq) If the Nernst equation for the above balanced reaction is E

_{\mathrm{cell}}

= E

_{\mathrm{cell}}^{\mathrm{o}}

-

\frac{\mathrm{R\,T}}{\mathrm{nF}}

\ell

n Q, Then the value of n is _________. (Nearest integer)

Q14·ChemistryNumericalJEE Main 2026

For strong electrolyte

\Lambda_m

increases slowly with dilution and can be represented by the equation

\Lambda_m = \Lambda^\circ_m - Ac^{1/2}

Molar conductivity values of the solutions of strong electrolyte AB at 18°C are given below : c [mol

L^{-1}

]: 0.04 | 0.09 | 0.16 | 0.25

\Lambda_m

[S

cm^2

mol^{-1}

]: 96.1 | 95.7 | 95.3 | 94.9 The value of constant A based on the above data [in S

cm^2

mol^{-1}

/

(mol/L)^{1/2}

] unit is ________.

Q15·ChemistryNumericalJEE Main 2026

A volume of x mL of 5 M

NaHCO_3

solution was mixed with 10 mL of 2 M

H_2CO_3

solution to make an electrolytic buffer. If the same buffer was used in the following electrochemical cell to record a cell potential of 235.3 mV, then the value of x = __________ mL (nearest integer).

Sn(s) | Sn(OH)_6^{2-}

(0.5 M)

| HSnO_2^-

(0.05 M)

| OH^- | Bi_2O_3(s) | Bi(s)

Consider upto one place of decimal for intermediate calculations [Given :

E^\circ_{HSnO_2^-|Sn(OH)_6^{2-}} = -0.9\,V

E^\circ_{Bi_2O_3|Bi} = -0.44V

pKa_{(H_2CO_3)} = 6.11

\frac{2.303RT}{F} = 0.059V

Anti\log(1.29) = 19.5

]

Q16·ChemistryNumericalJEE Main 2026

Electricity is passed through an acidic solution of

\mathrm{Cu^{2+}}

till all the

\mathrm{cu^{2+}}

was exhausted, leading to the deposition of 300 mg of Cu metal. However, a current of 600 mA was continued to pass through the same solution for another 28 minutes by keeping the total volume of the solution fixed at 200 mL. The total volume of oxygen evolved at STP during the entire process is ______ mL. (Nearest integer) [Given :

\mathrm{Cu^{2+}\left(aq\right)+2e^{-} \rightarrow Cu\left(s\right)\; E^{0}_{red} = +0.34\,V}

\mathrm{O_2\left(g\right)+4H^{+}+4e^{-} \rightarrow 2H_2O\; E^{0}_{red} = +1.23\,V}

Molar mass of Cu = 63.54 g mol

^{-1}

Molar mass of

\mathrm{O_2}

= 32 g mol

^{-1}

Faraday Constant = 96500 C mol

^{-1}

Molar volume at STP = 22.4 L ]

Q17·ChemistryNumericalJEE Main 2026

Molar conductivity of a weak acid HQ of concentration 0.18 M was found to be 1/30 of the molar conductivity of another weak acid HZ with concentration of 0.02 of M. If

\lambda^{0}_{\text{Q}^{-}}

happened to be equal with

\lambda^{0}_{\text{Z}^{-}}

, then the difference of the

\text{pK}_{\text{a}}

values of the two weak acids (

\text{pK}_{\text{a}}(\text{HQ})-\text{pK}_{\text{a}}(\text{HZ})

) is _______ (Nearest integer). [Given : degree of dissociation (

\alpha

) << 1 for both weak acids,

\lambda^{\circ}

: limiting molar conductivity of ions]

Q18·ChemistryNumericalJEE Main 2026

X and Y are the number of electrons involved, respectively during the oxidation of

\mathrm{I^{-}}

to

\mathrm{I_2}

and

\mathrm{S^{2-}}

to S by acidified

\mathrm{K_2Cr_2O_7}

. The value of X + Y is ______.

Q19·ChemistryNumericalJEE Main 2026

200 cc of x × 10

^{-3}

M potassium dichromate is required to oxidise 750 cc of 0.6 M Mohr’s salt solution in acidic medium. Here x =

Q20·ChemistrySingle correctJEE Main 2026

Consider the above electrochemical cell where a metal electrode (M) is undergoing redox reaction by forming M

^{+}

(M → M

^{+}

+ e). The cation M

^{+}

is present in two different concentrations c

_{1}

and c

_{2}

as shown above. Which of the following statement is correct for generating a positive cell potential?

(A)If c $_{1}$ is present at anode, then c $_{1}$ = c $_{2}$
(B)If c $_{1}$ is present at cathode, then c $_{1}$ < c $_{2}$
(C)If c $_{1}$ is present at cathode, then c $_{1}$ > c $_{2}$
(D)If c $_{1}$ is present at anode, then c $_{1}$ > c $_{2}$

Q21·ChemistrySingle correctJEE Main 2026

The oxidation state of chromium in the final product formed in the reaction between KI and acidified K

_{2}

Cr

_{2}

O

_{7}

solution is:

(A)+4
(B)+3
(C)+2
(D)+6

Q22·ChemistryNumericalJEE Main 2026

Consider the following electrochemical cell at 298K Pt

\left|\right.

HSnO

_2^-

(aq)

\left|\right.

Sn(OH)

_6^{2-}

(aq)

\left|\right.

Bi

_2

O

_3

(s)

\left|\right.

Bi(s). If the reaction quotient at a given time is 10

^6

, then the cell EMF (E

_{cell}

) is ________ × 10

^{-1}

V (Nearest integer). Given the standard half-cell reduction potential as

E^{0}_{Bi_2O_3/Bi,OH^-} = -0.44

V and

E^{0}_{Sn(OH)_6^{2-}/HSnO_2^-,OH} = -0.90

V

Q23·ChemistrySingle correctJEE Main 2026

Consider the following reduction processes :

Al^{3+} + 3e^{-} \rightarrow Al(s)

,

E^{o} = -1.66

V

Fe^{3+} + e^{-} \rightarrow Fe^{2+}

,

E^{o} = +0.77

V

Co^{3+} + e^{-} \rightarrow Co^{2+}

,

E^{o} = +1.81

V

Cr^{3+} + 3e^{-} \rightarrow Cr(s)

,

E^{o} = -0.74

V The tendency to act as reducing agent decreases in the order :

(A) $Al > Cr > Fe^{2+} > Co^{2+}$
(B) $Al > Fe^{2+} > Cr > Co^{2+}$
(C) $Al > Cr > Co^{2+} > Fe^{2+}$
(D) $Cr > Fe^{2+} > Al > Co^{2+}$

Q24·ChemistryNumericalJEE Main 2026

Consider the following electrochemical cell :

Pt\ |\ O_{2}(g)\ (1bar)\ |\ HCl\ (aq)\ ||\ M^{2+}(aq,\ 1.0\ M)\ |\ M(s)

The pH above which, oxygen gas would start to evolve at anode is ________ (nearest integer). [Given :

E^{0}_{M^{2+}/M} = 0.994V

,

E^{0}_{O_{2}/H_{2}O} = 1.23V

standard reduction potential and

\frac{RT}{F}(2.303) = 0.059

V at the given condition]

Q25·ChemistryNumericalJEE Main 2026

The pH and conductance of a weak acid (HX) was found to be 5 and 4 × 10

^{-5}

S, respectively. The conductance was measured under standard condition using a cell where the electrode plates having a surface area of 1 cm

^2

were at a distance of 15 cm apart. The value of the limiting molar conductivity is ……….. S m

^2

mol

^{-1}

. (nearest integer) (Given: degree of dissociation of the weak acid (a) << 1)

Q26·ChemistryNumericalJEE Main 2026

MX is a sparingly soluble salt that follows the given solubility equilibrium at 298 K

\text{MX(s)} \rightleftharpoons \text{M}^{+}\text{(aq)} + \text{X}^{-}\text{(aq)}

;

\text{K}_{\text{sp}} = 10^{-10}

If the standard reduction potential for

\text{M}^{+}\text{(aq)} \xrightarrow{+e^{-}} \text{M(s)}

is

\left(\text{E}^{\ominus}_{\text{M}^{+}/\text{M}}\right) = 0.79\text{V}

, then the value of the standard reduction potential for the metal/metal insoluble salt electrode

\text{E}^{\ominus}_{\text{X}^{-}/\text{MX(s)}/\text{M}}

is _________ mV. (nearest integer) [Given:

\frac{2.303\text{RT}}{\text{F}} = 0.059\text{V}

]

Q27·ChemistryNumericalJEE Advanced 2025

An electrochemical cell is fueled by the combustion of butane at 1 bar and 298 K. Its cell potential is

\frac{X}{F} \times 10^{3}

volts, where

F

is the Faraday constant. The value of X is _____. Use: Standard Gibbs energies of formation at 298 K are :

\Delta_{f}G^{o}_{CO_{2}}

=

-

394 kJ mol

^{-1}

;

\Delta_{f}G^{o}_{water}

=

-

237 kJ mol

^{-1}

;

\Delta_{f}G^{o}_{butane}

=

-

18 kJ mol

^{-1}

Q28·ChemistryNumericalJEE Advanced 2025

In an electrochemical cell, dichromate ions in aqueous acidic medium are reduced to

Cr^{3+}

. The current (in amperes) that flows through the cell for 48.25 minutes to produce 1 mole of

Cr^{3+}

is ______. Use: 1 Faraday = 96500 C

mol^{-1}

Q29·ChemistryIntegerJEE Main 2025

Consider the following half cell reaction:

Cr_2O_7^{2-}(aq)+6e^-+14H^+(aq)\to2Cr^{3+}(aq)+7H_2O(l)

. The reaction was conducted with the ratio of

\dfrac{[Cr^{3+}]^2}{[Cr_2O_7^{2-}]}=10^{-4}

. The pH value at which the EMF of the half cell will become zero is ___ (nearest integer value). [Given: standard half cell reduction potential

E^\circ_{Cr_2O_7^{2-}/Cr^{3+}}=1.33

V,

\dfrac{2.303RT}{F}=0.059

V]

Q30·ChemistryIntegerJEE Main 2025

1 Faraday electricity was passed through Cu

^{2+}

(1.5 M, 1 L)/Cu and 0.1 Faraday was passed through Ag

^+

(0.2 M, 1 L)/Ag electrolytic cells. After this the two cells were connected as shown (in the figure) to make an electrochemical cell. The emf of the cell thus formed at 298 K is ______ mV. (Given:

E^\circ_{Cu^{2+}/Cu}=0.34

V,

E^\circ_{Ag^+/Ag}=0.8

V,

\dfrac{2.303RT}{F}=0.06

V)

Q31·ChemistrySingle correctJEE Main 2025

1 M aqueous solution of each of

Cu(NO_3)_2

,

AgNO_3

,

Hg_2(NO_3)_2

and

Mg(NO_3)_2

are electrolysed using inert electrodes. Given:

E^{\ominus}_{Ag^+/Ag}=0.80

V,

E^{\ominus}_{Hg_2^{2+}/Hg}=0.79

V,

E^{\ominus}_{Cu^{2+}/Cu}=0.24

V and

E^{\ominus}_{Mg^{2+}/Mg}=-2.37

V. Statement (I): With increasing voltage, the sequence of deposition of metals on the cathode will be Ag, Hg and Cu. Statement (II): Magnesium will not be deposited at cathode instead oxygen gas will be evolved at the cathode. In the light of the above statements, choose the most appropriate answer from the options given below:

(A)Both statement I and statement II are incorrect
(B)Statement I is correct but statement II is incorrect
(C)Both statement I and statement II are correct
(D)Statement I is incorrect but statement II is correct

Q32·ChemistrySingle correctJEE Main 2025

Given below are two statements: Statement I: Mohr's salt is composed of only three types of ions-ferrous, ammonium and sulphate. Statement II: If the molar conductance at infinite dilution of ferrous, ammonium and sulphate ions are

x_1

,

x_2

and

x_3

S cm

^2

mol

^{-1}

, respectively then the molar conductance for Mohr's salt solution at infinite dilution would be given by

x_1+x_2+2x_3

. In the light of the given statements, choose the correct answer from the options given below:

(A)Both statements I and Statement II are false
(B)Statement I is false but Statement II is true
(C)Statement I is true but Statement II is false
(D)Both statements I and Statement II are true

Q33·ChemistrySingle correctJEE Main 2025

On charging the lead storage battery, the oxidation state of lead changes from

x_1

to

y_1

at the anode and from

x_2

to

y_2

at the cathode. The values of

x_1, y_1, x_2, y_2

are respectively:

(A) $+4, +2, 0, +2$
(B) $+2, 0, +2, +4$
(C) $0, +2, +4, +2$
(D) $+2, 0, 0, +4$

Q34·ChemistryIntegerJEE Main 2025

KMnO_4

acts as an oxidising agent in acidic medium. 'X' is the difference between the oxidation states of Mn in reactant and product. 'Y' is the number of 'd' electrons present in the brown red precipitate formed at the end of the action test with neutral ferric chloride. The value of

X+Y

is ______.

Q35·ChemistryIntegerJEE Main 2025

The molar conductance of an infinitely dilute solution of ammonium chloride was found to be

185\ S\,cm^2\,mol^{-1}

and the ionic conductance of hydroxyl and chloride ions are 170 and

70\ S\,cm^2\,mol^{-1}

, respectively. If molar conductance of 0.02 M solution of ammonium hydroxide is

85.5\ S\,cm^2\,mol^{-1}

, its degree of dissociation is given by

x \times 10^{-1}

. The value of x is ______ (Nearest integer).

Q36·ChemistrySingle correctJEE Main 2025

The standard cell potential

(E^{\ominus}_{cell})

of a fuel cell based on the oxidation of methanol in air that has been used to power a television relay station is measured as 1.21 V. The standard half cell reduction potential for

O_2

\left(E^{\circ}_{O_2/H_2O}\right)

is 1.229 V. Choose the correct statement:

(A)The standard half cell reduction potential for the reduction of $CO_2$ $\left(E^{\circ}_{CO_2/CH_3OH}\right)$ is 19 mV
(B)Oxygen is formed at the anode.
(C)Reactants are fed at one go to each electrode.
(D)Reduction of methanol takes place at the cathode.

Q37·ChemistrySingle correctJEE Main 2025

Correct order of limiting molar conductivity for cations in water at 298 K is:

(A) $H^+ > Na^+ > K^+ > Ca^{2+} > Mg^{2+}$
(B) $H^+ > Ca^{2+} > Mg^{2+} > K^+ > Na^+$
(C) $Mg^{2+} > H^+ > Ca^{2+} > K^+ > Na^+$
(D) $H^+ > Na^+ > Ca^{2+} > Mg^{2+} > K^+$

Q38·ChemistryIntegerJEE Main 2025

Consider the following electrochemical cell at standard conditions:

Au(s)\,|\,QH_2\,|\,Q\,||\,NH_4X(0.01\,M)\,||\,Ag^+(1\,M)\,|\,Ag(s)

,

E^\circ_{cell}=+0.4

V. The couple

QH_2/Q

represents the quinhydrone electrode, whose half-cell reaction is

Q+2e^-+2H^+\to QH_2

,

E^\circ_{Q/QH_2}=+0.7

V. Given

E^\circ_{Ag^+/Ag}=+0.8

V and

\dfrac{2.303RT}{F}=0.06

V, the

pK_b

value of the ammonium halide salt

(NH_4X)

used here is ______ (nearest integer).

Q39·ChemistryIntegerJEE Main 2025

A

0.2\%

(w/v) solution of NaOH is measured to have resistivity

870.0\ m\Omega\,m

. The molar conductivity of the solution will be ______

\times10^2\ mS\,dm^2\,mol^{-1}

. (Nearest integer)

Q40·ChemistrySingle correctJEE Main 2025

O_2

gas will be evolved as a product of electrolysis of: (A) an aqueous solution of

AgNO_3

using silver electrodes. (B) an aqueous solution of

AgNO_3

using platinum electrodes. (C) a dilute solution of

H_2SO_4

using platinum electrodes. (D) a high concentration solution of

H_2SO_4

using platinum electrodes. Choose the correct answer from the options given below:

(A)(B) and (C) only
(B)(A) and (D) only
(C)(B) and (D) only
(D)(A) and (C) only

Q41·ChemistrySingle correctJEE Main 2025

For a

Mg\,|\,Mg^{2+}(aq)\,||\,Ag^{+}(aq)\,|\,Ag

the correct Nernst Equation is:

(A) $E_{cell}=E^\circ_{cell}-\dfrac{RT}{2F}\ln\dfrac{[Ag^{+}]}{[Mg^{2+}]}$
(B) $E_{cell}=E^\circ_{cell}-\dfrac{RT}{2F}\ln\dfrac{[Mg^{2+}]}{[Ag^{+}]^{2}}$
(C) $E_{cell}=E^\circ_{cell}-\dfrac{RT}{2F}\ln\dfrac{[Mg^{2+}]}{[Ag^{+}]}$
(D) $E_{cell}=E^\circ_{cell}-\dfrac{RT}{2F}\ln\dfrac{[Ag^{+}]^{2}}{[Mg^{2+}]}$

Q42·ChemistrySingle correctJEE Main 2025

Match List-I (Applications) with List-II (Batteries/Cell). Choose the correct answer from the options given below:

List-I (Applications)	List-II (Batteries/Cell)
A.Transistors	I.Anode – Zn/Hg ; Cathode – HgO + C
B.Hearing aids	II.Hydrogen fuel cell
C.Invertors	III.Anode – Zn ; Cathode – Carbon
D.Apollo space ship	IV.Anode – Pb ; Cathode – Pb \| PbO₂

(A)(A)-(III), (B)-(I), (C)-(IV), (D)-(II)
(B)(A)-(III), (B)-(II), (C)-(IV), (D)-(I)
(C)(A)-(IV), (B)-(III), (C)-(II), (D)-(I)
(D)(A)-(II), (B)-(III), (C)-(IV), (D)-(I)

Q43·ChemistrySingle correctJEE Main 2025

0.1 M solution of KI reacts with excess of

H_2SO_4

and

KIO_3

solution. According to the equation

5I^-+IO_3^-+6H^+\rightarrow 3I_2+3H_2O

. Identify the correct statements: (A) 200 mL of KI solution reacts with 0.004 mol of

KIO_3

. (B) 200 mL of KI solution reacts with 0.006 mol of

H_2SO_4

. (C) 0.5 L of KI solution produced 0.005 mol of

I_2

. (D) Equivalent weight of

KIO_3

is equal to

\dfrac{\text{Molecular weight}}{5}

. Choose the correct answer from the options given below:

(A)(A) and (D) only
(B)(B) and (C) only
(C)(A) and (B) only
(D)(C) and (D) only

Q44·ChemistrySingle correctJEE Main 2025

The molar conductivity of a weak electrolyte when plotted against the square root of its concentration, which of the following is expected to be observed?

(A)A small decrease in molar conductivity is observed at infinite dilution.
(B)A small increase in molar conductivity is observed at infinite dilution.
(C)Molar conductivity increases sharply with increase in concentration.
(D)Molar conductivity decreases sharply with increase in concentration.

Q45·ChemistrySingle correctJEE Main 2025

Given below are two statements: Statement I: In oxalic acid v/s KMnO

_4

(in the presence of dil H

_2

SO

_4

) titration the solution needs to be heated initially to 60°C, but no heating is required in Ferrous ammonium sulphate (FAS) vs KMnO

_4

titration (in the presence of dil H

_2

SO

_4

). Statement II: In oxalic acid vs KMnO

_4

titration, the initial formation of MnSO

_4

takes place at high temperature, which then acts as catalyst for further reaction. In the case of FAS vs KMnO

_4

, heating oxidizes Fe

^{2+}

into Fe

^{3+}

by oxygen of air and error may be introduced in the experiment. In the light of the above statements, choose the correct answer from the options given below:

(A)Statement I is false but Statement II is true
(B)Both Statement I and Statement II are true
(C)Statement I is true but Statement II is false
(D)Both Statement I and Statement II are false

Q46·ChemistryIntegerJEE Main 2025

Given below is the plot of the molar conductivity vs

\sqrt{\text{concentration}}

for KCl in aqueous solution (shown in figure). If, for the higher concentration of KCl solution, the resistance of the conductivity cell is 100

\Omega

, then the resistance of the same cell with the dilute solution is 'x'

\Omega

. The value of x is _______ (Nearest integer)

Q47·ChemistryIntegerJEE Main 2025

Electrolysis of 600 mL aqueous solution of NaCl for 5 min changes the pH of the solution to 12. The current in Amperes used for the given electrolysis is ______. (Nearest integer)

Q48·ChemistrySingle correctJEE Main 2025

Match List-I (Redox Reaction) with List-II (Type of Redox Reaction). Choose the correct answer from the options given below:

List-I (Redox Reaction)	List-II (Type of Redox Reaction)
A.CH $_4$ (g) + 2O $_2$ (g) $\xrightarrow{\Delta}$ CO $_2$ (g) + 2H $_2$ O(l)	I.Disproportionation reaction
B.2NaH(s) $\xrightarrow{\Delta}$ 2Na(s) + H $_2$ (g)	II.Combination reaction
C.V $_2$ O $_5$ (s) + 5Ca(s) $\xrightarrow{\Delta}$ 2V(s) + 5CaO(s)	III.Decomposition reaction
D.2H $_2$ O $_2$ (aq) $\xrightarrow{\Delta}$ 2H $_2$ O(l) + O $_2$ (g)	IV.Displacement reaction

(A)(A)-(II), (B)-(III), (C)-(IV), (D)-(I)
(B)(A)-(II), (B)-(III), (C)-(I), (D)-(IV)
(C)(A)-(III), (B)-(IV), (C)-(I), (D)-(II)
(D)(A)-(IV), (B)-(I), (C)-(II), (D)-(III)

Q49·ChemistrySingle correctJEE Main 2025

For the given cell

Fe^{2+}(aq)+Ag^+(aq)\to Fe^{3+}(aq)+Ag(s)

. The standard cell potential of the above reaction is. Given :

Ag^++e^-\to Ag

,

E^0=x

V;

Fe^{2+}+2e^-\to Fe

,

E^0=y

V;

Fe^{3+}+3e^-\to Fe

,

E^0=z

V.

(A) $x+y-z$
(B) $x+2y-3z$
(C) $y-2x$
(D) $x+2y$

Q50·ChemistrySingle correctJEE Main 2025

Based on the data given below:

E^0_{Cr_2O_7^{2-}/Cr^{3+}}=1.33

V,

E^0_{Cl_2/Cl^-}=1.36

V,

E^0_{MnO_4^-/Mn^{2+}}=1.51

V,

E^0_{Cr^{3+}/Cr}=-0.74

V. The strongest reducing agent is :

(A) $Mn^{2+}$
(B) $Cr$
(C) $MnO_4^-$
(D) $Cl^-$

Q51·ChemistrySingle correctJEE Main 2025

Standard electrode potentials for a few half cells are mentioned below:

E^\circ_{Cu^{2+}/Cu}=0.34

V,

E^\circ_{Zn^{2+}/Zn}=-0.76

V,

E^\circ_{Ag^+/Ag}=0.80

V,

E^\circ_{Mg^{2+}/Mg}=-2.37

V. Which one of the following cells gives the most negative value of

\Delta G^\circ

?

(A) $Zn\,|\,Zn^{2+}(1M)\,||\,Ag^+(1M)\,|\,Ag$
(B) $Zn\,|\,Zn^{2+}(1M)\,||\,Mg^{2+}(1M)\,|\,Mg$
(C) $Ag\,|\,Ag^+(1M)\,||\,Mg^{2+}(1M)\,|\,Mg$
(D) $Cu\,|\,Cu^{2+}(1M)\,||\,Ag^+(1M)\,|\,Ag$

Q52·ChemistrySingle correctJEE Main 2025

In the diagram below, the standard electrode potentials are given in volts (over the arrow).

FeO_4^{2-}\xrightarrow{+2.0V}Fe^{3+}\xrightarrow{0.8V}Fe^{2+}\xrightarrow{-0.5V}Fe^{0}

. The value of

E^{\circ}_{FeO_4^{2-}/Fe^{2+}}

is

(A)1.7 V
(B)1.2 V
(C)2.1 V
(D)1.4 V

Q53·ChemistrySingle correctJEE Main 2025

Given below are two statements: Statement (I): Corrosion is an electrochemical phenomenon in which pure metal acts as an anode and impure metal as a cathode. Statement (II): The rate of corrosion is more in alkaline medium than in acidic medium. In the light of the above statements, choose the correct answer from the options given below:

(A)Both Statement I and Statement II are false
(B)Statement I is false but Statement II is true
(C)Both Statement I and Statement II are true
(D)Statement I is true but Statement II is false

Q54·ChemistrySingle correctJEE Main 2025

Which of the following electrolytes can be used to obtain H₂S₂O₈ by the process of electrolysis?

(A)Dilute solution of sodium sulphate
(B)Dilute solution of sulphuric acid
(C)Concentrated solution of sulphuric acid
(D)Acidified dilute solution of sodium sulphate

Q55·ChemistrySingle correctJEE Main 2025

A solution of aluminium chloride is electrolysed for 30 minutes using a current of 2 A. The amount of aluminium deposited at the cathode is ______. (Given: molar masses of aluminium and chlorine are 27 g mol⁻¹ and 35.5 g mol⁻¹ respectively; Faraday constant = 96500 C mol⁻¹)

(A)1.660 g
(B)1.007 g
(C)0.336 g
(D)0.441 g

Q56·ChemistryMultiple correctJEE Advanced 2024

An aqueous solution of hydrazine (

N_2H_4

) is electrochemically oxidized by

O_2

, thereby releasing chemical energy in the form of electrical energy. One of the products generated from the electrochemical reaction is

N_2(g)

. Choose the correct statement(s) about the above process (A)

OH^-

ions react with

N_2H_4

at the anode to form

N_2(g)

and water, releasing 4 electrons to the anode. (B) At the cathode,

N_2H_4

breaks to

N_2(g)

and nascent hydrogen released at the electrode reacts with oxygen to form water. (C) At the cathode, molecular oxygen gets converted to

OH^-

. (D) Oxides of nitrogen are major by-products of the electrochemical process.

(A) $OH^-$ ions react with $N_2H_4$ at the anode to form $N_2(g)$ and water, releasing 4 electrons to the anode.
(B)At the cathode, $N_2H_4$ breaks to $N_2(g)$ and nascent hydrogen released at the electrode reacts with oxygen to form water.
(C)At the cathode, molecular oxygen gets converted to $OH^-$ .
(D)Oxides of nitrogen are major by-products of the electrochemical process.

Q57·ChemistrySingle correctJEE Advanced 2024

In a conductometric titration, small volume of titrant of higher concentration is added stepwise to a larger volume of titrate of much lower concentration, and the conductance is measured after each addition. The limiting ionic conductivity

\left(\Lambda_{0}\right)

values (in mS m

^{2}

mol

^{-1}

) for different ions in aqueous solutions are given below: Ag

^{+}

6.2; K

^{+}

7.4; Na

^{+}

5.0; H

^{+}

35.0; NO

_{3}^{-}

7.2; Cl

^{-}

7.6; SO

_{4}^{2-}

16.0; OH

^{-}

19.9; CH

_{3}

COO

^{-}

4.1 For different combinations of titrates and titrants given in List-I, the graphs of 'conductance' versus 'volume of titrant' are given in List-II. Match each entry List-I with the appropriate entry in List-II and choose the correct option.

List-I	List-II
P.Titrate: KCl Titrant: AgNO $_{3}$	1.see figure
Q.Titrate: AgNO $_{3}$ Titrant: KCl	2.see figure
R.Titrate: NaOH Titrant: HCl	3.see figure
S.Titrate: NaOH Titrant: CH $_{3}$ COOH	4.see figure
	5.see figure

(A)(P) $\to$ (4), (Q) $\to$ (3), (R) $\to$ (2), (S) $\to$ (5)
(B)(P) $\to$ (2), (Q) $\to$ (4), (R) $\to$ (3), (S) $\to$ (1)
(C)(P) $\to$ (3), (Q) $\to$ (4), (R) $\to$ (2), (S) $\to$ (5)
(D)(P) $\to$ (4), (Q) $\to$ (3), (R) $\to$ (2), (S) $\to$ (1)

Q58·ChemistrySingle correctJEE Main 2024

The molar conductivity for electrolytes A and B are plotted against

C^{1/2}

as shown below. Electrolytes A and B respectively are :

(A)A: Weak electrolyte, B: weak electrolyte
(B)A: Strong electrolyte, B: strong electrolyte
(C)A: Weak electrolyte, B: strong electrolyte
(D)A: Strong electrolyte, B: weak electrolyte

Q59·ChemistryNumericalJEE Main 2024

The standard reduction potentials at 298 K for the following half cells are given below:

Cr_2O_7^{2-} + 14H^+ + 6e^- \rightarrow 2Cr^{3+} + 7H_2O

,

E^\circ = 1.33

V

Fe^{3+}(aq) + 3e^- \rightarrow Fe

,

E^\circ = -0.04

V

Ni^{2+}(aq) + 2e^- \rightarrow Ni

,

E^\circ = -0.25

V

Ag^+(aq) + e^- \rightarrow Ag

,

E^\circ = 0.80

V

Au^{3+}(aq) + 3e^- \rightarrow Au

,

E^\circ = 1.40

V Consider the given electrochemical reactions, The number of metal(s) which will be oxidized be

Cr_2O_7^{2-}

, in aqueous solution is _____.

Q60·ChemistrySingle correctJEE Main 2024

Which out of the following is a correct equation to show change in molar conductivity with respect to concentration of a weak electrolyte, if the symbols carry their usual meaning:

(A) $\Lambda_m^{2}C - K_a(\Lambda_m^{0})^{2} + K_a\Lambda_m\Lambda_m^{0} = 0$
(B) $\Lambda_m = \Lambda_m^{0} + AC^{1/2} = 0$
(C) $\Lambda_m = \Lambda_m^{0} - AC^{1/2} = 0$
(D) $\Lambda_m^{2}C + K_a(\Lambda_m^{0})^{2} - K_a\Lambda_m\Lambda_m^{0} = 0$

Q61·ChemistrySingle correctJEE Main 2024

Match List-I (Cell) with List-II (Use / Property / Reaction). Choose the correct answer from the options given below:

List-I (Cell)	List-II (Use / Property / Reaction)
A.Leclanche cell	I.Converts energy of combustion into electrical energy
B.Ni-Cd cell	II.Does not involve any ion in solution and is used in hearing aids
C.Fuel cell	III.Rechargeable
D.Mercury cell	IV.Reaction at anode $Zn \rightarrow Zn^{2+} + 2e^{-}$

(A)A-I, B-II, C-III, D-IV
(B)A-III, B-I, C-IV, D-II
(C)A-IV, B-III, C-I, D-II
(D)A-II, B-III, C-IV, D-I

Q62·ChemistrySingle correctJEE Main 2024

Given below are two statements : Statement (I) : The oxidation state of an element in a particular compound is the charge acquired by its atom on the basis of electron gain enthalpy consideration from other atoms in the molecule. Statement (II) :

p\pi

-

p\pi

bond formation is more prevalent in second period elements over other periods. In the light of the above statements, choose the most appropriate answer from the options given below :

(A)Both Statement I and Statement II are incorrect
(B)Statement I is correct but Statement II is incorrect
(C)Both Statement I and Statement II are correct
(D)Statement I is incorrect but Statement II is correct

Q63·ChemistrySingle correctJEE Main 2024

The emf of the cell

\text{Tl}\,|\,\text{Tl}^+(0.001\,\text{M})\,||\,\text{Cu}^{2+}(0.01\,\text{M})\,|\,\text{Cu}

is 0.83 V at 298 K. It could be increased by:

(A)increasing concentration of $\text{Tl}^+$ ions
(B)increasing concentration of both $\text{Tl}^+$ and $\text{Cu}^{2+}$ ions
(C)decreasing concentration of both $\text{Tl}^+$ and $\text{Cu}^{2+}$ ions
(D)increasing concentration of $\text{Cu}^{2+}$ ions

Q64·ChemistrySingle correctJEE Main 2024

Thiosulphate reacts differently with iodine and bromine in the reactions given below:

2S_2O_3^{2-}+I_2\to S_4O_6^{2-}+2I^-

;

S_2O_3^{2-}+5Br_2+5H_2O\to 2SO_4^{2-}+4Br^-+10H^+

. Which of the following statement justifies the above dual behaviour of thiosulphate?

(A)Bromine undergoes oxidation and iodine undergoes reduction by iodine in these reactions
(B)Bromine undergoes oxidation by bromine and reduction by iodine in these reactions
(C)Bromine is a stronger oxidant than iodine
(D)Bromine is a weaker oxidant than iodine

Q65·ChemistrySingle correctJEE Main 2024

The reaction

\tfrac{1}{2}\text{H}_2(g)+\text{AgCl}(s)\to \text{H}^+(aq)+\text{Cl}^-(aq)+\text{Ag}(s)

occurs in which of the following galvanic cell:

(A) $\text{Pt}\,|\,\text{H}_2(g)\,|\,\text{HCl(soln.)}\,|\,\text{AgCl}(s)\,|\,\text{Ag}$
(B) $\text{Pt}\,|\,\text{H}_2(g)\,|\,\text{HCl(soln.)}\,|\,\text{AgNO}_3(aq)\,|\,\text{Ag}$
(C) $\text{Pt}\,|\,\text{H}_2(g)\,|\,\text{KCl(soln.)}\,|\,\text{AgCl}(s)\,|\,\text{Ag}$
(D) $\text{Ag}\,|\,\text{AgCl}(s)\,|\,\text{KCl(soln.)}\,|\,\text{AgNO}_3(aq.)\,|\,\text{Ag}$

Q66·ChemistrySingle correctJEE Main 2024

Iron (III) catalyses the reaction between iodide and persulphate ions, in which A.

Fe^{3+}

oxidises the iodide ion; B.

Fe^{2+}

oxidises the persulphate ion; C.

Fe^{2+}

reduces the iodide ion; D.

Fe^{3+}

reduces the persulphate ion. Choose the most appropriate answer from the options given below:

(A)B and C only
(B)B only
(C)A only
(D)A and D only

Q67·ChemistrySingle correctJEE Main 2024

Match List-I (redox reactions) with List-II (the type of redox reaction). Choose the correct answer:

List-I (Reaction)	List-II (Type of redox reaction)
A. $N_{2(g)} + O_{2(g)} \rightarrow 2NO_{(g)}$	I.Decomposition
B. $2Pb(NO_3)_{2(s)} \rightarrow 2PbO_{(s)} + 4NO_{2(g)} + O_{2(g)}$	II.Displacement
C. $2Na_{(s)} + 2H_2O_{(l)} \rightarrow 2NaOH_{(aq.)} + H_{2(g)}$	III.Disproportionation
D. $2NO_{2(g)} + 2\,^{-}OH_{(aq.)} \rightarrow NO_{2(aq.)}^{-} + NO_{3(aq.)}^{-} + H_2O_{(l)}$	IV.Combination

(A)(A)-(I), (B)-(II), (C)-(III), (D)-(IV)
(B)(A)-(III), (B)-(II), (C)-(I), (D)-(IV)
(C)(A)-(II), (B)-(III), (C)-(IV), (D)-(I)
(D)(A)-(IV), (B)-(I), (C)-(II), (D)-(III)

Q68·ChemistrySingle correctJEE Main 2024

How can an electrochemical cell be converted into an electrolytic cell?

(A)Applying an external opposite potential greater than $E^0_{cell}$
(B)Reversing the flow of ions in salt bridge.
(C)Applying an external opposite potential lower than $E^0_{cell}$ .
(D)Exchanging the electrodes at anode and cathode.

Q69·ChemistrySingle correctJEE Main 2024

A conductivity cell with two electrodes (dark side) is half filled with infinitely dilute aqueous solution of a weak electrolyte (cell shown in the figure). If volume is doubled by adding more water at constant temperature, the molar conductivity of the cell will:

(A)increase sharply
(B)remain same or can not be measured accurately
(C)decrease sharply
(D)depend upon type of electrolyte

Q70·ChemistrySingle correctJEE Main 2024

For the electrochemical cell

M\,|\,M^{2+}\,||\,X\,|\,X^{2-}

, if

E^\circ_{(M^{2+}/M)} = 0.46

V and

E^\circ_{(X/X^{2-})} = 0.34

V, which of the following is correct?

(A) $E_{cell} = -0.80$ V
(B) $M + X \rightarrow M^{2+} + X^{2-}$ is a spontaneous reaction
(C) $M^{2+} + X^{2-} \rightarrow M + X$ is a spontaneous reaction
(D) $E_{cell} = 0.80$ V

Q71·ChemistrySingle correctJEE Main 2024

The quantity of silver deposited when one coulomb of charge is passed through

\text{AgNO}_3

solution is:

(A)0.1 g atom of silver
(B)1 chemical equivalent of silver
(C)1 g of silver
(D)1 electrochemical equivalent of silver

Q72·ChemistrySingle correctJEE Main 2024

The reaction at the cathode in the cells commonly used in clocks involves:

(A)reduction of Mn from +4 to +3
(B)oxidation of Mn from +3 to +4
(C)reduction of Mn from +7 to +2
(D)oxidation of Mn from +7 to +2

Q73·ChemistrySingle correctJEE Main 2024

What pressure (bar) of

H_2

would be required to make emf of hydrogen electrode zero in pure water at

25^\circ C

?

(A) $10^{-14}$
(B) $10^{-7}$
(C) $1$
(D) $0.5$

Q74·ChemistrySingle correctJEE Main 2024

One of the commonly used electrode is calomel electrode. Under which of the following categories calomel electrode comes?

(A)Metal – Insoluble Salt – Anion electrodes
(B)Oxidation – Reduction electrodes
(C)Gas – Ion electrodes
(D)Metal ion – Metal electrodes

Q75·ChemistryNumericalJEE Main 2024

Only

2\,mL

of

KMnO_4

solution of unknown molarity is required to reach the end point of a titration of

20\,mL

of oxalic acid

(2\,M)

in acidic medium. The molarity of

KMnO_4

solution should be ___ M.

Q76·ChemistrySingle correctJEE Main 2024

Fuel cell, using hydrogen and oxygen as fuels, A. has been used in spaceship, B. has an efficiency of 40% to produce electricity, C. uses aluminium as catalysts, D. is eco-friendly, E. is actually a type of Galvanic cell only. Choose the correct answer from the options given below:

(A)A, B, C only
(B)A, B, D only
(C)A, B, D, E only
(D)A, D, E only

Q77·ChemistrySingle correctJEE Main 2024

For a strong electrolyte, a plot of molar conductivity against (concentration)

^{1/2}

is a straight line, with a negative slope, the correct unit for the slope is

(A) $\text{S cm}^2\,\text{mol}^{-3/2}\,\text{L}^{1/2}$
(B) $\text{S cm}^2\,\text{mol}^{-1}\,\text{L}^{1/2}$
(C) $\text{S cm}^2\,\text{mol}^{-3/2}\,\text{L}$
(D) $\text{S cm}^2\,\text{mol}^{-3/2}\,\text{L}^{-1/2}$

Q78·ChemistrySingle correctJEE Main 2024

Which of the following reactions are disproportionation reactions? (A)

Cu^+\to Cu^{2+}+Cu

(B)

3MnO_4^{2-}+4H^+\to 2MnO_4^-+MnO_2+2H_2O

(C)

2KMnO_4\to K_2MnO_4+MnO_2+O_2

(D)

2MnO_4^-+3Mn^{2+}+2H_2O\to 5MnO_2+4H^+

. Choose the correct answer from the options given below:

(A)(A), (B)
(B)(B), (C), (D)
(C)(A), (B), (C)
(D)(A), (D)

Q79·ChemistryNumericalJEE Main 2024

Consider the following redox reaction:

\text{MnO}_4^-+\text{H}^++\text{H}_2\text{C}_2\text{O}_4\rightleftharpoons\text{Mn}^{2+}+\text{H}_2\text{O}+\text{CO}_2

. The standard reduction potentials are given as below (

E^{\circ}_{\text{red}}

):

E^{\circ}_{\text{MnO}_4^-/\text{Mn}^{2+}}=+1.51

V,

E^{\circ}_{\text{CO}_2/\text{H}_2\text{C}_2\text{O}_4}=-0.49

V. If the equilibrium constant of the above reaction is given as

K_{\text{eq}}=10^x

, then the value of

x=

__________ (nearest integer).

Q80·ChemistrySingle correctJEE Main 2024

In acidic medium,

K_2Cr_2O_7

shows oxidising action as represented in the half reaction

Cr_2O_7^{2-}+XH^++Ye^-\to 2Cr^{3+}+ZH_2O

.

X

,

Y

,

Z

and

A

are respectively:

(A) $8,6,4$ and $Cr_2O_5$
(B) $14,7,6$ and $Cr^{3+}$
(C) $8,4,6$ and $Cr_2O_5$
(D) $14,6,7$ and $Cr^{3+}$

Q81·ChemistryNumericalJEE Main 2024

The amount of electricity in Coulomb required for the oxidation of 1 mol of

\text{H}_2\text{O}

to

\text{O}_2

is __________

\times 10^5

C.

Q82·ChemistryNumericalJEE Main 2024

The potential for the given half cell at

298K

is

(-)\,\underline{\quad}\times10^{-2}\,V

.

2H^+_{(aq)}+2e^-\to H_2(g)

;

[H^+]=1M

,

P_{H_2}=2

atm. (Given:

2.303\,RT/F=0.06\,V

,

\log2=0.3

)

Q83·ChemistrySingle correctJEE Main 2024

Given below are two statements: Statement-I:

S_8

solid undergoes disproportionation reaction under alkaline conditions to form

S^{2-}

and

S_2O_3^{2-}

. Statement-II:

ClO_4^-

can undergo disproportionation reaction under acidic condition. In the light of the above statements, choose the most appropriate answer from the options given below:

(A)Statement I is correct but statement II is incorrect.
(B)Statement I is incorrect but statement II is correct
(C)Both Statement I and Statement II are incorrect
(D)Both Statement I and statement II are correct

Q84·ChemistryNumericalJEE Main 2024

One Faraday of electricity liberates

x\times10^{-1}

gram atom of copper from copper sulphate, x is ______.

Q85·ChemistryNumericalJEE Main 2024

Number of moles of

H^+

ions required by 1 mole of

MnO_4^-

to oxidise oxalate ion to

CO_2

is ______.

Q86·ChemistrySingle correctJEE Main 2024

Identify the factor from the following that does not affect electrolytic conductance of a solution.

(A)The nature of the electrolyte added.
(B)The nature of the electrode used.
(C)Concentration of the electrolyte.
(D)The nature of solvent used.

Q87·ChemistrySingle correctJEE Main 2024

The metals that are employed in the battery industries are A. Fe B. Mn C. Ni D. Cr E. Cd Choose the correct answer from the options given below:

(A)B, C and E only
(B)A, B, C, D and E
(C)A, B, C and D only
(D)B, D and E only

Q88·ChemistrySingle correctJEE Main 2024

Reduction potential of ions are given below:

E^\circ_{ClO_4^-}=1.19

V,

E^\circ_{IO_4^-}=1.65

V,

E^\circ_{BrO_4^-}=1.74

V. The correct order of their oxidising power is:

(A) $ClO_4^- > IO_4^- > BrO_4^-$
(B) $ClO_4^- > BrO_4^- > IO_4^-$
(C) $BrO_4^- > ClO_4^- > IO_4^-$
(D) $BrO_4^- > IO_4^- > ClO_4^-$

Q89·ChemistryNumericalJEE Main 2024

2MnO_4^- + bI^- + cH_2O \to xI_2 + yMnO_2 + zOH^-

. If the above equation is balanced with integer coefficients, the value of

z

is ___

Q90·ChemistryNumericalJEE Main 2024

Total number of species from the following which can undergo disproportionation reaction is ______.

H_2O_2

,

ClO_3^-

,

P_4

,

Cl_2

,

Ag

,

Cu^{+1}

,

F_2

,

NO_2

,

K^+

Q91·ChemistrySingle correctJEE Main 2024

In alkaline medium,

MnO_4^-

oxidises

I^-

to

(A) $IO_4^-$
(B) $IO^-$
(C) $I_2$
(D) $IO_3^-$

Q92·ChemistryNumericalJEE Main 2024

The mass of zinc produced by the electrolysis of zinc sulphate solution with a steady current of 0.015 A for 15 minutes is ______

\times10^{-4}

g. (Atomic mass of zinc = 65.4 amu)

Q93·ChemistryNumericalJEE Main 2024

A constant current was passed through a solution of

AuCl_4^-

ion between gold electrodes. After a period of 10.0 minutes, the increase in mass of cathode was 1.314 g. The total charge passed through the solution is ___

\times10^{-2}

F. (Given atomic mass of Au = 197)

Q94·ChemistrySingle correctJEE Main 2024

Chlorine undergoes disproportionation in alkaline medium as shown below :

a\,Cl_2(g)+b\,OH^-(aq)\to c\,ClO^-(aq)+d\,Cl^-(aq)+e\,H_2O(l)

. The values of a, b, c and d in a balanced redox reaction are respectively :

(A)1, 2, 1 and 1
(B)2, 2, 1 and 3
(C)3, 4, 4 and 2
(D)2, 4, 1 and 3

Q95·ChemistryNumericalJEE Main 2024

The hydrogen electrode is dipped in a solution of pH = 3 at

25^\circ

C. The potential of the electrode will be __________

\times10^{-2}

V.

\left(\dfrac{2.303RT}{F}=0.059\text{ V}\right)

Q96·ChemistryNumericalJEE Main 2024

The mass of silver (Molar mass of Ag : 108 g\,mol

^{-1}

) displaced by a quantity of electricity which displaces 5600 mL of

\text{O}_2

at S.T.P. will be __________ g.

Q97·ChemistrySingle correctJEE Main 2024

Which of the following statements is not correct about rusting of iron ?

(A)Coating of iron surface by tin prevents rusting, even if the tin coating is peeling off.
(B)When pH lies above 9 or 10, rusting of iron does not take place.
(C)Dissolved acidic oxides $SO_2$ , $NO_2$ in water act as catalyst in the process of rusting.
(D)Rusting of iron is envisaged as setting up of electrochemical cell on the surface of iron object.

Q98·ChemistryNumericalJEE Main 2024

1 mole of PbS is oxidised by "X" moles of

O_3

to get "Y" moles of

O_2

.

X+Y

is __________.

Q99·ChemistrySingle correctJEE Advanced 2023

Plotting

1/\Lambda_\mathrm{m}

against

c\Lambda_\mathrm{m}

for aqueous solutions of a monobasic weak acid (HX) resulted in a straight line with y-axis intercept of P and slope of S. The ratio P/S is [

\Lambda_\mathrm{m}

= molar conductivity

\Lambda_\mathrm{m}^{0}

= limiting molar conductivity c = molar concentration

\mathrm{K_a}

= dissociation constant of HX]

(A) $\mathrm{K_a}\Lambda_\mathrm{m}^{0}$
(B) $\mathrm{K_a}\Lambda_\mathrm{m}^{0}/2$
(C) $2\mathrm{K_a}\Lambda_\mathrm{m}^{0}$
(D) $1/\left(\mathrm{K_a}\Lambda_\mathrm{m}^{0}\right)$

Q100·ChemistryIntegerJEE Advanced 2023

Consider the following molecules:

\mathrm{Br_3O_8}

,

\mathrm{F_2O}

,

\mathrm{H_2S_4O_6}

,

\mathrm{H_2S_5O_6}

, and

\mathrm{C_3O_2}

. Count the number of atoms existing in their zero oxidation state in each molecule. Their sum is____.

Q101·ChemistryIntegerJEE Advanced 2023

\mathrm{H_2S}

(5 moles) reacts completely with acidified aqueous potassium permanganate solution. In this reaction, the number of moles of water produced is

\mathbf{x}

, and the number of moles of electrons involved is

\mathbf{y}

. The value of

(\mathbf{x} + \mathbf{y})

is ____.

Q102·ChemistryNumericalJEE Main 2023

The number of correct statements from the following is _______ (A) Conductivity always decreases with decrease in concentration for both strong and weak electrolytes. (B) The number of ions per unit volume that carry current in a solution increases on dilution. (C) Molar conductivity increases with decrease in concentration. (D) The variation in molar conductivity is different for strong and weak electrolytes. (E) For weak electrolytes, the change in molar conductivity with dilution is due to decrease in degree of dissociation.

Q103·ChemistryNumericalJEE Main 2023

The total change in the oxidation state of manganese involved in the reaction of

KMnO_4

and potassium iodide in the acidic medium is _______

Q104·ChemistryNumericalJEE Main 2023

See the following chemical reaction:

Cr_2O_7^{2-} + XH^+ + 6Fe^{2+} \rightarrow YCr^{3+} + 6Fe^{3+} + ZH_2O

. The sum of X, Y and Z is ____.

Q105·ChemistryNumericalJEE Main 2023

At 298 K, the standard reduction potential for

Cu^{2+}/Cu

electrode is 0.34 V. Given:

K_{sp}

of

Cu(OH)_2 = 1 \times 10^{-20}

. Take

\dfrac{2.303RT}{F} = 0.059

V. The reduction potential at pH = 14 for the above couple is

(-)x \times 10^{-2}

V. The value of x is ____.

Q106·ChemistryNumericalJEE Main 2023

KMnO_{4}

is titrated with ferrous ammonium sulphate hexahydrate in presence of dilute

H_{2}SO_{4}

. Number of water molecules produced for

2

molecules of

KMnO_{4}

is _____.

Q107·ChemistryNumericalJEE Main 2023

A metal surface of

100\,cm^{2}

area has to be coated with nickel layer of thickness

0.001\,mm

. A current of

2\,A

was passed through a solution of

Ni(NO_{3})_{2}

for

'x'

seconds to coat the desired layer. The value of

x

is _____ (Nearest integer).

(\rho_{Ni}

(density of Nickel) is

10\,g\,mL^{-1}

. Molar mass of Nickel is

60\,g\,mol^{-1},\,F=96500\,C\,mol^{-1})

Q108·ChemistrySingle correctJEE Main 2023

For lead storage battery, pick the correct statement. A. During charging of battery, PbSO

_4

on anode is converted into PbO

_2

. B. During discharging of battery, PbSO

_4

on cathode is converted into PbO

_2

. C. Lead storage battery consists of grid of lead packed with PbO

_2

as anode. D. Lead storage battery has ~38% solution of sulphuric acid as an electrolyte. Choose the correct answer from the options given below:

(A)A, D only
(B)B, C, D only
(C)A, B, D only
(D)B, C only

Q109·ChemistryNumericalJEE Main 2023

The number of correct statements from the following is ____. A.

E_{cell}

is an intensive parameter. B. A negative

E^\circ

means that the redox couple is a stronger reducing agent than the

H^+/H_2

couple. C. The amount of electricity required for oxidation or reduction depends on the stoichiometry of the electrode reaction. D. The amount of chemical reaction which occurs at any electrode during electrolysis by a current is proportional to the quantity of electricity passed through the electrolyte.

Q110·ChemistryNumericalJEE Main 2023

KClO_3 + 6FeSO_4 + 3H_2SO_4 \rightarrow KCl + 3Fe_2(SO_4)_3 + 3H_2O

The above reaction was studied at 300 K by monitoring the concentration of

FeSO_4

in which initial concentration was 10 M and after half an hour became 8.8 M. The rate of production of

Fe_2(SO_4)_3

is __________

\times 10^{-6}

mol

L^{-1}

s^{-1}

. (Nearest integer)

Q111·ChemistryNumericalJEE Main 2023

In an electrochemical reaction of lead, at standard temperature, if

E^0_{(Pb^{2+}/Pb)} = m

Volt and

E^0_{(Pb^{4+}/Pb)} = n

Volt, then the value of

E^0_{(Pb^{2+}/Pb^{4+})}

is given by

m - xn

. The value of x is __________. (Nearest integer)

Q112·ChemistrySingle correctJEE Main 2023

Given below are two statements. Statement I: Aqueous solution of K

_2

Cr

_2

O

_7

is preferred as a primary standard in volumetric analysis as compared to Na

_2

Cr

_2

O

_7

aqueous solution. Statement II: K

_2

Cr

_2

O

_7

has a higher solubility in water than Na

_2

Cr

_2

O

_7

. In the light of the above statements, choose the correct answer from the options given below:

(A)Both Statement I and Statement II are true
(B)Both Statement I and Statement II are false
(C)Statement I is true but Statement II is false
(D)Statement I is false but Statement II is true

Q113·ChemistryNumericalJEE Main 2023

FeO_4^{2-}\xrightarrow{-2.2V}Fe^{3+}\xrightarrow{-0.70V}Fe^{2+}\xrightarrow{-0.45V}Fe^{0}

.

E^0_{FeO_4^{2-}/Fe^{2+}}

is

x\times10^{-1}

V. The value of x is _________.

Q114·ChemistryNumericalJEE Main 2023

In alkaline medium, the reduction of the permanganate anion involves a gain of _______ electrons.

Q115·ChemistryNumericalJEE Main 2023

The specific conductance of

0.0025

M acetic acid is

5\times10^{-5}

S cm

^{-1}

at a certain temperature. The dissociation constant of acetic acid is _______

\times10^{-7}

(nearest integer). (Consider limiting molar conductivity of

\text{CH}_3\text{COOH}

as

400

S cm

^2

mol

^{-1}

).

Q116·ChemistrySingle correctJEE Main 2023

2IO_3^- + xI^- + 12H^+ \rightarrow 6I_2 + 6H_2O

What is the value of x?

(A)12
(B)2
(C)6
(D)10

Q117·ChemistrySingle correctJEE Main 2023

The reaction

\frac{1}{2}H_2(g) + AgCl(s) \rightleftharpoons H^+(aq) + Cl^-(aq) + Ag(s)

occurs in which of the given galvanic cell.

(A) $Pt | H_2(g) | KCl(sol^n) | AgCl(s) | Ag$
(B) $Pt | H_2(g) | HCl(sol^n) | AgCl(s) | Ag$
(C) $Ag | AgCl(s) | KCl(sol^n) | AgCl(s) | Ag$
(D) $Pt | H_2(g) | HCl(sol^n) | AgNO_3(sol^n) | Ag$

Q118·ChemistryNumericalJEE Main 2023

The number of incorrect statements from the following is ____. A. The electrical work that a reaction can perform at constant pressure and temperature is equal to the reaction Gibbs energy. B.

E^0_{cell}

is dependent on the pressure. C.

\left(\dfrac{dE^0_{cell}}{dT}\right)=\dfrac{\Delta_r S^0}{nF}

. D. A cell is operating reversibly if the cell potential is exactly balanced by an opposing source of potential difference.

Q119·ChemistryNumericalJEE Main 2023

The sum of the oxidation states of the metals in

Fe(CO)_5

,

VO^{2+}

and

WO_3

is ____.

Q120·ChemistrySingle correctJEE Main 2023

The product, which is not obtained during the electrolysis of brine solution is

(A)NaOH
(B) $Cl_2$
(C) $H_2$
(D)HCl

Q121·ChemistryNumericalJEE Main 2023

The standard reduction potentials at 298 K for the following half cells are given:

NO_3^- + 4H^+ + 3e^- \rightarrow NO(g) + 2H_2O

,

E^0 = 0.97

V;

V^{2+}(aq) + 2e^- \rightarrow V

,

E^0 = -1.19

V;

Fe^{3+}(aq) + 3e^- \rightarrow Fe

,

E^0 = -0.04

V;

Ag^+(aq) + e^- \rightarrow Ag(s)

,

E^0 = 0.80

V;

Au^{3+}(aq) + 3e^- \rightarrow Au(s)

,

E^0 = 1.40

V. The number of metal(s) which will be oxidized by

NO_3^-

in aqueous solution is ____.

Q122·ChemistrySingle correctJEE Main 2023

During the reaction of permanganate with thiosulphate, the change in oxidation number of manganese occurs by value of 3. Identify which of the below medium will favour the reaction.

(A)aqueous acidic
(B)aqueous neutral
(C)both aqueous acidic and neutral
(D)both aqueous acidic and faintly alkaline

Q123·ChemistrySingle correctJEE Main 2023

The standard electrode potential of

M^{+}/M

in aqueous solution does not depend on:

(A)Ionisation of a solid metal atom
(B)Sublimation of a solid metal
(C)Ionisation of a gaseous metal atom
(D)Hydration of a gaseous metal ion

Q124·ChemistryNumericalJEE Main 2023

Sum of oxidation states of bromine in bromic acid and perbromic acid is _______ .

Q125·ChemistryNumericalJEE Main 2023

At what pH, the given half cell

\text{MnO}_4^-(0.1\,\text{M})\,|\,\text{Mn}^{2+}(0.001\,\text{M})

will have electrode potential of

1.282

V? _______ (Nearest Integer). (Given

E^\circ_{\text{MnO}_4^-|\text{Mn}^{2+}}=1.54

V,

\tfrac{2.303RT}{F}=0.059

V).

Q126·ChemistryNumericalJEE Main 2023

1\times10^{-5}

M

AgNO_3

is added to

1

L of saturated solution of AgBr. The conductivity of this solution at

298

K is _________

\times10^{-9}

S m

^{-1}

. [Given:

K_{SP}(AgBr)=4.9\times10^{-13}

at

298

K,

\lambda^0_{Ag^+}=6\times10^{-3}

,

\lambda^0_{Br^-}=8\times10^{-3}

,

\lambda^0_{NO_3^-}=7\times10^{-3}

S m

^2

mol

^{-1}

]

Q127·ChemistrySingle correctJEE Main 2023

Which one of the following statements is correct for electrolysis of brine solution?

(A) $Cl_2$ is formed at cathode
(B) $O_2$ is formed at cathode
(C) $H_2$ is formed at anode
(D) $OH^-$ is formed at cathode

Q128·ChemistryNumericalJEE Main 2023

The resistivity of a 0.8M solution of an electrolyte is

5\times10^{-3}\,\Omega

cm. Its molar conductivity is _________

\times10^4\,\Omega^{-1}cm^2mol^{-1}

(Nearest integer)

Q129·ChemistrySingle correctJEE Main 2023

When

Cu^{2+}

ion is treated with KI, a white precipitate, X appears in solution. The solution is titrated with sodium thiosulphate, the compound Y is formed. X and Y respectively are

(A)X = $CuI_2$ , Y = $Na_2S_4O_6$
(B)X = $CuI_2$ , Y = $Na_2S_2O_3$
(C)X = $Cu_2I_2$ , Y = $Na_2S_4O_5$
(D)X = $Cu_2I_2$ , Y = $Na_2S_4O_6$

Q130·ChemistryNumericalJEE Main 2023

The electrode potential of the following cell at 298 K,

X\,|\,X^{2+}(0.001\,M)\,\|\,Y^{2+}(0.01\,M)\,|\,Y

, is _______

\times10^{-2}

V (nearest integer). (Given:

E^{0}_{X^{2+}|X}=-2.36

V;

E^{0}_{Y^{2+}|Y}=+0.36

V;

\dfrac{2.303RT}{F}=0.06

V)

Q131·ChemistryNumericalJEE Main 2023

Consider the cell Pt

_{(s)}

|H

_2

(g, 1 atm)|H

^+

(aq, 1M)||Fe

^{3+}

(aq), Fe

^{2+}

(aq)|Pt(s). When the potential of the cell is

0.712

V at

298

K, the ratio [Fe

^{2+}

]/[Fe

^{3+}

] is _________ (Nearest integer). Given: Fe

^{3+}

+ e

^-

= Fe

^{2+}

, E

^0

= 0.771 V,

\dfrac{2.303RT}{F}=0.06

V

Q132·ChemistryNumericalJEE Main 2023

The number of electrons involved in the reduction of permanganate to manganese dioxide in acidic medium is

Q133·ChemistrySingle correctJEE Main 2023

KMnO_4

oxidises

I^-

in acidic and neutral/faintly alkaline solution, respectively, to:

(A) $IO_3^-\ \&\ IO_3^-$
(B) $I_2\ \&\ IO_3^-$
(C) $I_2\ \&\ I_2$
(D) $IO_3^-\ \&\ I_2$

Q134·ChemistryNumericalJEE Main 2023

The equilibrium constant for the reaction

Zn(s)+Sn^{2+}(aq)\rightleftharpoons Zn^{2+}(aq)+Sn(s)

is

1\times10^{20}

at

298\,K

. The magnitude of standard electrode potential of

Sn/Sn^{2+}

if

E^\circ_{Zn^{2+}/Zn}=-0.76\,V

is _____

\times10^{-2}\,V

(Nearest integer). Given:

\dfrac{2.303RT}{F}=0.059\,V

.

Q135·ChemistrySingle correctJEE Main 2023

The standard electrode potential (

M^{3+}/M^{2+}

) for V, Cr, Mn and Co are

-0.26

V,

-0.41

V,

+1.57

V and

+1.97

V, respectively. The metal ions which can liberate H

_2

from a dilute acid are:

(A)Mn $^{2+}$ and Co $^{2+}$
(B)Cr $^{2+}$ and Co $^{2+}$
(C)V $^{2+}$ and Cr $^{2+}$
(D)V $^{2+}$ and Mn $^{2+}$

Q136·ChemistryNumericalJEE Main 2023

Following figure shows dependence of molar conductance of two electrolytes on concentration.

\Lambda_m^\circ

is the limiting molar conductivity. The number of incorrect statement(s) from the following is ________ . (A)

\Lambda_m^\circ

for electrolyte A is obtained by extrapolation (B) For electrolyte B,

\Lambda_m

vs

\sqrt{c}

graph is a straight line with intercept equal to

\Lambda_m^\circ

(C) At infinite dilution, the value of degree of dissociation approaches zero for electrolyte B. (D)

\Lambda_m^\circ

for any electrolyte A or B can be calculated using

\lambda^\circ

for individual ions.

Q137·ChemistryNumericalJEE Main 2023

Pt(s)|H_2(g)(1\,bar)||H^+(aq)(1\,M)\,||\,M^{3+}(aq), M^+(aq)|Pt(s)

The

E_{cell}

for the given cell is 0.1115 V at 298 K when

\frac{[M^+(aq)]}{[M^{3+}(aq)]} = 10^a

. The value of

a

is Given :

E^\theta\,M^{3+}/M^+ = 0.2

V

\frac{2.303RT}{F} = 0.059

V

Q138·ChemistrySingle correctJEE Main 2023

Which one among the following metals is the weakest reducing agent?

(A)Li
(B)K
(C)Rb
(D)Na

Q139·ChemistryNumericalJEE Main 2023

Consider the cell

Pt(s)\,|\,H_2(g)\,(1\,atm)\,|\,H^+(aq, [H^+]=1)\,||\,Fe^{3+}(aq), Fe^{2+}(aq)\,|\,Pt(s)

. Given

E^{\circ}_{Fe^{3+}/Fe^{2+}}=0.771

V and

E^{\circ}_{H^+/H_2}=0

V, T = 298 K. If the potential of the cell is 0.712 V, the ratio of concentration of

Fe^{2+}

to

Fe^{3+}

is _______ (nearest integer).

Q140·ChemistrySingle correctJEE Main 2023

Potassium dichromate acts as a strong oxidizing agent in acidic solution. During this process, the oxidation state change from

(A)+2 to +1
(B)+3 to +1
(C)+6 to +2
(D)+6 to +3

Q141·ChemistryNumericalJEE Main 2023

At 298 K, a 1 litre solution containing 10 mmol of

\text{Cr}_2\text{O}_7^{2-}

and 100 mmol of

\text{Cr}^{3+}

shows a pH of 3.0. Given:

\text{Cr}_2\text{O}_7^{2-}\to\text{Cr}^{3+}

;

E^\circ=1.330

V and

\tfrac{2.303RT}{F}=0.059

V. The potential for the half cell reaction is

x\times10^{-3}

V. The value of

x

is _______ .

Q142·ChemistrySingle correctJEE Main 2023

Choose the correct representation of conductometric titration of benzoic acid vs sodium hydroxide.

(A)(1)
(B)(2)
(C)(3)
(D)(4)

Q143·ChemistryNumericalJEE Advanced 2022

The reduction potential

\left(\mathrm{E}^{0}\text{, in V}\right)

of

\mathrm{MnO_4^-(aq)\,/\,Mn(s)}

is

\left[\text{Given}: \mathrm{E}^{0}_{\left(\mathrm{MnO_4^-(aq)/MnO_2((s))}\right)} = 1.68\,\mathrm{V};\ \mathrm{E}^{0}_{\left(\mathrm{MnO_2(s)/Mn^{2+}(aq)}\right)} = 1.21\,\mathrm{V};\ \mathrm{E}^{0}_{\left(\mathrm{Mn^{2+}(aq)/Mn((s))}\right)} = -1.03\,\mathrm{V}\right]

Q144·ChemistryIntegerJEE Advanced 2022

Consider the strong electrolytes

\mathrm{Z_mX_n}

,

\mathrm{U_mY_p}

and

\mathrm{V_mX_n}

. Limiting molar conductivity

\left(\Lambda^0\right)

of

\mathrm{U_mY_p}

and

\mathrm{V_mX_n}

are 250 and 440

\mathrm{S\ cm^2\ mol^{-1}}

, respectively. The value of (m + n + p) is____. The plot of molar conductivity

\left(\Lambda\right)

of

\mathrm{Z_mX_n}

vs

\mathrm{c^{1/2}}

is given below.

Q145·ChemistryNumericalJEE Advanced 2022

The treatment of an aqueous solution of 3.74 g of

\mathrm{Cu(NO_3)_2}

with excess KI results in a brown solution along with the formation of a precipitate. Passing

\mathrm{H_2S}

through this brown solution gives another precipitate

\mathbf{X}

. The amount of

\mathbf{X}

(in g) is ________. [Given: Atomic mass of H = 1, N = 14, O = 16, S = 32, K = 39, Cu = 63, I = 127]

Q146·ChemistrySingle correctJEE Main 2022

In neutral or faintly alkaline medium,

KMnO_{4}

being a powerful oxidant can oxidize, thiosulphate almost quantitatively, to sulphate. In this reaction overall change in oxidation state of manganese will be :

(A)5
(B)1
(C)0
(D)3

Q147·ChemistryNumericalJEE Main 2022

Resistance of a conductivity cell (cell constant 129

m^{-1}

) filled with 74.5 ppm solution of KCl is 100 Ω (labelled as solution 1). When the same cell is filled with KCl solution of 149 ppm, the resistance is 50 Ω (labelled as solution 2). The ratio of molar conductivity of solution 1 and solution 2 is i.e.

\frac{\Lambda_{1}}{\Lambda_{2}} = x \times 10^{-3}

. The value of x is ______. (Nearest integer) Given, molar mass of KCl is 74.5 g

mol^{-1}

Q148·ChemistryNumericalJEE Main 2022

For a cell, Cu(s) |Cu

^{2+}

(0.001M| |Ag

^{+}

(0.01M)| Ag(s) the cell potential is found to be 0.43 V at 298 K. The magnitude of standard electrode potential for Cu

^{2+}

/Cu is ___

\times 10^{-2}

V. [Given :

E^{\ominus}_{Ag^{+}/Ag}

= 0.80V and

\frac{2.303RT}{F}

= 0.06V]

Q149·ChemistrySingle correctJEE Main 2022

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R Assertion A : Permanganate titrations are not performed in presence of hydrochloric acid. Reason R : Chlorine is formed as a consequence of oxidation of hydrochloric acid. In the light of the above statements, choose the correct answer from the options given below

(A)Both A and R are true and R is the correct explanation of A
(B)Both A and R are true but R is NOT the correct explanation of A
(C)A is true but R is false
(D)A is false but R is true

Q150·ChemistrySingle correctJEE Main 2022

Match List-I with List-II. Choose the correct answer from the options given below :

List-I	List-II
A.Cd(s) + 2Ni(OH) $_3$ (s) → CdO(s) + 2Ni(OH) $_2$ (s) + H $_2$ O( $l$ )	I.Primary battery
B.Zn(Hg) + HgO(s) → ZnO(s) + Hg( $l$ )	II.Discharging of secondary battery
C.2PbSO $_4$ (s) + 2H $_2$ O( $l$ ) → Pb(s) + PbO $_2$ (s) + 2H $_2$ SO $_4$ (aq)	III.Fuel cell
D.2H $_2$ (g) + O $_2$ (g) → 2H $_2$ O( $l$ )	IV.Charging of secondary battery

(A)(A) – (I), (B) – (II), (C) – (III), (D) – (IV)
(B)(A) – (IV), (B) – (I), (C) – (II), (D) – (III)
(C)(A) – (II), (B) – (I), (C) – (IV), (D) – (III)
(D)(A) – (II), (B) – (I), (C) – (III), (D) – (IV)

Q151·ChemistryNumericalJEE Main 2022

On reaction with stronger oxidizing agent like

\mathrm{KIO_4}

, hydrogen peroxide oxidizes with the evolution of

\mathrm{O_2}

. The oxidation number of I in

\mathrm{KIO_4}

changes to _____.

Q152·ChemistryNumericalJEE Main 2022

20 mL of 0.02 M

K_{2}Cr_{2}O_{7}

solution is used for the titration of 10 mL of

Fe^{2+}

solution in the acidic medium. The molarity of

Fe^{2+}

solution is ______

\times 10^{-2}

M. (Nearest Integer)

Q153·ChemistrySingle correctJEE Main 2022

Given below are two statements: Statement I: For KI, molar conductivity increases steeply with dilution. Statement II: For carbonic acid, molar conductivity increases slowly with dilution. In the light of the above statements, choose the correct answer from the options given below:

(A)Both Statement I and Statement II are true
(B)Both Statement I and Statement II are false
(C)Statement I is true but Statement II is false
(D)Statement I is false but Statement II is true

Q154·ChemistryNumericalJEE Main 2022

In the titration of

KMnO_{4}

and oxalic acid in acidic medium, the change in oxidation number of carbon at the end point is______

Q155·ChemistryNumericalJEE Main 2022

The amount of charge in F (Faraday) required to obtain one mole of iron from Fe

_3

O

_4

is _____. (Nearest Integer)

Q156·ChemistrySingle correctJEE Main 2022

The dark purple colour of KMnO

_4

disappears in the titration with oxalic acid in acidic medium. The overall change in the oxidation number of manganese in the reaction is :

(A)5
(B)1
(C)7
(D)2

Q157·ChemistryNumericalJEE Main 2022

20 mL of 0.02 M hypo solution is used for the titration of 10 mL of copper sulphate solution, in the presence of excess of KI using starch as an indicator. The molarity of

Cu^{2+}

is found to be _____ ×

10^{-2}

M [nearest integer] Given :

2Cu^{2+}

+

4I^{-}

→

Cu_{2}I_{2}

+

I_{2}

I_{2}

+

2S_{2}O_{3}^{2-}

→

2I^{-}

+

S_{4}O_{6}^{2-}

Q158·ChemistrySingle correctJEE Main 2022

Which of the given reactions is not an example of disproportionation reaction ?

(A)2H $_2$ O $_2$ → 2H $_2$ O + O $_2$
(B)2NO $_2$ + H $_2$ O → HNO $_3$ + HNO $_2$
(C)MnO $_4^-$ + 4H $^+$ + 3e $^-$ → MnO $_2$ + 2H $_2$ O
(D)3MnO $_4^{2-}$ + 4H $^+$ → 2MnO $_4^-$ + MnO $_2$ + 2H $_2$ O

Q159·ChemistrySingle correctJEE Main 2022

The reaction of

H_{2}O_{2}

with potassium permanganate in acidic medium leads to the formation of mainly:

(A) $Mn^{2+}$
(B) $Mn^{4+}$
(C) $Mn^{3+}$
(D) $Mn^{6+}$

Q160·ChemistryNumericalJEE Main 2022

A dilute solution of sulphuric acid is electrolysed using a current of 0.10 A for 2 hours to produce hydrogen and oxygen gas. The total volume of gases produced at STP is _______

cm^3

. (Nearest integer) [Given : Faraday constant F = 96500 C

mol^{-1}

at STP, molar volume of an ideal gas is 22.7 L

mol^{-1}

]

Q161·ChemistryNumericalJEE Main 2022

The cell potential for the given cell at 298 K Pt | H

_2

(g,1 bar) | H

^+

(aq) || Cu

^{2+}

(aq) | Cu(s) is 0.31V. The pH of the acidic solution is found to be 3, whereas the concentration of Cu

^{2+}

is 10

^{-x}

M. The value of x is ______. (Given: E

^{\ominus}_{Cu^{2+}/Cu}

= 0.34 V and

\frac{2.303RT}{F}

= 0.06V)

Q162·ChemistryNumericalJEE Main 2022

A 2.0 g sample containing

MnO_2

is treated with HCl liberating

Cl_2

. The

Cl_2

gas is passed into a solution of KI and 60.0 mL of 0.1 M

Na_2S_2O_3

is required to titrate the liberated iodine. The percentage of

MnO_2

in the sample is __________. (Nearest integer) [Atomic masses (in u) Mn = 55; Cl = 35.5; O = 16, I = 127, Na = 23, K = 39, S = 32]

Q163·ChemistryNumericalJEE Main 2022

The solubility product of a sparingly soluble salt

A_2X_3

is

1.1 \times 10^{-23}

. If specific conductance of the solution is

3 \times 10^{-5}

S

m^{-1}

, the limiting molar conductivity of the solution is x

\times 10^{-3}

S

m^{2}

mol^{-1}

. The value of x is __________.

Q164·ChemistryNumericalJEE Main 2022

The quantity of electricity in Faraday needed to reduce 1 mol of

Cr_2O_7^{2-}

to

Cr^{3+}

is __________.

Q165·ChemistryNumericalJEE Main 2022

For the given reactions Sn

^{2+}

+ 2e

^-

→ Sn Sn

^{4+}

+ 4e

^-

→ Sn The electrode potentials are;

E^{o}_{Sn^{2+}/Sn}

= –0.140 V and

E^{o}_{Sn^{4+}/Sn}

= 0.010 V. The magnitude of standard electrode potential for Sn

^{4+}

/Sn

^{2+}

i.e.

E^{o}_{Sn^{4+}/Sn^{2+}}

is ______ × 10

^{-2}

V. (Nearest integer)

Q166·ChemistryNumericalJEE Main 2022

0.01 M KMnO

_4

solution was added to 20.0 mL of 0.05 M Mohr's salt solution through a burette. The initial reading of 50 mL burette is zero. The volume of KMnO

_4

solution left in the burette after the end point is ______ mL. (nearest integer)

Q167·ChemistryNumericalJEE Main 2022

For the reaction taking place in the cell: Pt(s) | H

_2

(g) | H

^+

(aq) || Ag

^+

(aq) | Ag(s) E

^o_{Cell}

= +0.5332 V. The value of

\Delta_f

G

^0

is _________ kJ mol

^{-1}

. (in nearest integer)

Q168·ChemistryNumericalJEE Main 2022

The limiting molar conductivities of NaI,

NaNO_{3}

and

AgNO_{3}

are 12.7, 12.0 and 13.3 mS m

^{2}

mol

^{-1}

, respectively (all at 25°C). The limiting molar conductivity of AgI at this temperature is _____ mS m

^{2}

mol

^{-1}

Q169·ChemistrySingle correctJEE Main 2022

The

\left(\frac{\partial E}{\partial T}\right)_{P}

of different types of half cells are as follows : A B C D

1 \times 10^{-4}

2 \times 10^{-4}

0.1 \times 10^{-4}

0.2 \times 10^{-4}

(Where E is the electromotive force) Which of the above half cells would be preferred to be used as reference electrode ?

(A)A
(B)B
(C)C
(D)D

Q170·ChemistrySingle correctJEE Main 2022

Which one of the following is an example of disproportionation reaction?

(A) $3MnO_4^{2-} + 4H^+ \rightarrow 2MnO_4^- + MnO_2 + 2H_2O$
(B) $MnO_4^{2-} + 4H^+ + 4e^- \rightarrow MnO_2 + 2H_2O$
(C) $10I^- + 2MnO_4^- + 16H^+ \rightarrow 2Mn^{2+} + 8H_2O + 5I_2$
(D) $8MnO_4^- + 3S_2O_3^{2-} + H_2O \rightarrow 8MnO_2 + 6SO_4^{2-} + 2OH^-$

Q171·ChemistryNumericalJEE Main 2022

Cu(s) +

Sn^{2+}

(0.001M) →

Cu^{2+}

(0.01M) + Sn(s) The Gibbs free energy change for the above reaction at 298 K is x ×

10^{-1}

kJ

mol^{-1}

; The value of x is_______. [nearest integer] [Given :

E^{\ominus}_{Cu^{2+}/Cu}

= 0.34 V;

E^{\ominus}_{Sn^{2+}/Sn}

= −0.14 V; F = 96500 C

mol^{-1}

]

Q172·ChemistryNumericalJEE Main 2022

A solution of Fe

_2

(SO

_4

)

_3

is electrolyzed for 'x' min with a current of 1.5 A to deposit 0.3482 g of Fe. The value of x is______. [nearest integer] Given : 1 F = 96500 C mol

^{-1}

Atomic mass of Fe = 56 g mol

^{-1}

Q173·ChemistrySingle correctJEE Main 2022

The correct order of reduction potentials of the following pairs is A. Cl

_2

/Cl

^-

B. I

_2

/I

^-

C. Ag

^+

/Ag D. Na

^+

/Na E. Li

^+

/Li Choose the correct answer from the options given below.

(A)A > C > B > D > E
(B)A > B > C > D > E
(C)A > C > B > E > D
(D)A > B > C > E > D

Q174·ChemistryNumericalJEE Main 2022

In a cell, the following reactions take place

Fe^{2+} \rightarrow Fe^{3+}e^{-}

E^{o}_{Fe^{3+}/Fe^{2+}} = 0.77

V

2I^{-} \rightarrow I_2 + 2e^{-}

E^{o}_{I_2/I^{-}} = 0.54

V The standard electrode potential for the spontaneous reaction in the cell is x ×

10^{-2}

V 298 K. The value of x is __________ (Nearest Integer)

Q175·ChemistryNumericalJEE Main 2022

The cell potential for the following cell

\mathrm{Pt}\,|\,\mathrm{H}_2(g)\,|\,\mathrm{H}^{+}(aq)\,||\,\mathrm{Cu}^{2+}(0.01\,\mathrm{M})\,|\,\mathrm{Cu}(s)

is 0.576 V at 298 K. The pH of the solution is ___. (Nearest integer)

Q176·ChemistryMultiple correctJEE Advanced 2021

Some standard electrode potentials at 298 K are given below: Pb

^{2+}

/Pb — −0.13 V Ni

^{2+}

/Ni — −0.24 V Cd

^{2+}

/Cd — −0.40 V Fe

^{2+}

/Fe — −0.44 V To a solution containing 0.001 M of

\mathbf{X}^{2+}

and 0.1 M of

\mathbf{Y}^{2+}

, the metal rods

\mathbf{X}

and

\mathbf{Y}

are inserted (at 298 K) and connected by a conducting wire. This resulted in dissolution of

\mathbf{X}

. The correct combination(s) of

\mathbf{X}

and

\mathbf{Y}

, respectively, is (are) (Given: Gas constant, R = 8.314 J K

^{-1}

mol

^{-1}

, Faraday constant, F = 96500 C mol

^{-1}

)

(A)Cd and Ni
(B)Cd and Fe
(C)Ni and Pb
(D)Ni and Fe

Q177·ChemistryNumericalJEE Advanced 2021

At 298 K, the limiting molar conductivity of a weak monobasic acid is 4 × 10

^{2}

S cm

^{2}

mol

^{-1}

. At 298 K, for an aqueous solution of the acid the degree of dissociation of α and the molar conductivity is y × 10

^{2}

S cm

^{2}

mol

^{-1}

. At 298 K, upon 20 times dilution with water, the molar conductivity of the solution becomes 3y×10

^{2}

S cm

^{2}

mol

^{-1}

. The value of

\alpha

is ______.

Q178·ChemistryNumericalJEE Advanced 2021

At 298 K, the limiting molar conductivity of a weak monobasic acid is 4 × 10

^{2}

S cm

^{2}

mol

^{-1}

. At 298 K, for an aqueous solution of the acid the degree of dissociation of α and the molar conductivity is y × 10

^{2}

S cm

^{2}

mol

^{-1}

. At 298 K, upon 20 times dilution with water, the molar conductivity of the solution becomes 3y×10

^{2}

S cm

^{2}

mol

^{-1}

. The value of

\mathbf{y}

is ______.

Q179·ChemistryNumericalJEE Advanced 2021

A sample (5.6 g) containing iron is completely dissolved in cold dilute HCl to prepare a 250 mL of solution. Titration of 25.0 mL of this solution requires 12.5 mL of 0.03 M KMnO

_{4}

solution to reach the end point. Number of moles of Fe

^{2+}

present in 250 mL solution is x × 10

^{-2}

(consider complete dissolution of FeCl

_{2}

). The amount of iron present in the sample of y% by weight. (Assume : KMnO

_{4}

reacts only with Fe

^{2+}

in the solution Use : Molar mass of iron as 56 g mol

^{-1}

) The value of

\mathbf{x}

is ______.

Q180·ChemistryNumericalJEE Advanced 2021

A sample (5.6 g) containing iron is completely dissolved in cold dilute HCl to prepare a 250 mL of solution. Titration of 25.0 mL of this solution requires 12.5 mL of 0.03 M KMnO

_{4}

solution to reach the end point. Number of moles of Fe

^{2+}

present in 250 mL solution is x × 10

^{-2}

(consider complete dissolution of FeCl

_{2}

). The amount of iron present in the sample of y% by weight. (Assume : KMnO

_{4}

reacts only with Fe

^{2+}

in the solution Use : Molar mass of iron as 56 g mol

^{-1}

) The value of

\mathbf{y}

is ______.

Q181·ChemistryNumericalJEE Main 2021

If the conductivity of mercury at 0°C is 1.07 × 10

^{6}

S m

^{-1}

and the resistance of a cell containing mercury is 0.243 Ω, then the cell constant of the cell is x × 10

^{4}

m

^{-1}

. The value of x is ______ .(Nearest integer)

Q182·ChemistrySingle correctJEE Main 2021

Match List-I with List-II List-I (Parameter) (a) Cell constant (b) Molar conductivity (c) Conductivity (d) Degree of dissociation of electrolyte List-II (Unit) (i)

\mathrm{S\ cm^2\ mol^{-1}}

(ii) Dimensionless (iii)

\mathrm{m^{-1}}

(iv)

\mathrm{\Omega^{-1}\ m^{-1}}

Choose the most appropriate answer from the options given below :

(A)(a)-(iii), (b)-(i), (c)-(iv), (d)-(ii)
(B)(a)-(iii), (b)-(i), (c)-(ii), (d)-(iv)
(C)(a)-(i), (b)-(iv), (c)-(iii), (d)-(ii)
(D)(a)-(ii), (b)-(i), (c)-(iii), (d)-(iv)

Q183·ChemistryNumericalJEE Main 2021

Consider the following cell reaction :

\mathrm{Cd_{(s)}+Hg_2SO_{4(s)}+\frac{9}{5}H_2O_{(l)}\rightleftharpoons CdSO_4.\frac{9}{5}H_2O_{(s)}+2Hg_{(l)}}

The value of

\mathrm{E^{0}_{cell}}

is 4.315 V at 25°C. If

\Delta

H° =

-

825.2 kJ mol

^{-1}

, the standard entropy change

\Delta

S° in J K

^{-1}

is __. (Nearest integer) [Given : Faraday constant = 96487 C mol

^{-1}

]

Q184·ChemistryNumericalJEE Main 2021

When 10 mL of an aqueous solution of

KMnO_4

was titrated in acidic medium, equal volume of 0.1 M of an aqueous solution of ferrous sulphate was required for complete discharge of colour. The strength of

KMnO_4

in grams per litre is ________

\times 10^{-2}

. (Nearest integer) [Atomic mass of K = 39, Mn = 55, O = 16]

Q185·ChemistryNumericalJEE Main 2021

The resistance of a conductivity cell with cell constant 1.14 cm

^{-1}

, containing 0.001 M KCl at 298 K is 1500 Ω. The molar conductivity of 0.001 M KCl solution at 298 K in S cm

^{2}

mol

^{-1}

is _____ . (Integer answer)

Q186·ChemistrySingle correctJEE Main 2021

In polythionic acid,

\mathrm{H_2S_xO_6}

(x = 3 to 5) the oxidation state(s) of sulphur is/are :

(A)+ 5 only
(B)+ 6 only
(C)+ 3 and + 5 only
(D)0 and + 5 only

Q187·ChemistrySingle correctJEE Main 2021

Given below are two statements : Statement I : The limiting molar conductivity of KCl (strong electrolyte) is higher compared to that of

\mathrm{CH_3COOH}

(weak electrolyte). Statement II : Molar conductivity decreases with decrease in concentration of electrolyte. In the light of the above statements, choose the most appropriate answer from the options given below :

(A)Statement I is true but Statement II is false.
(B)Statement I is false but Statement II is true.
(C)Both Statement I and Statement II are true.
(D)Both Statement I and Statement II are false.

Q188·ChemistryNumericalJEE Main 2021

These are physical properties of an element (A) Sublimation enthalpy (B) Ionisation enthalpy (C) Hydration enthalpy (D) Electron gain enthalpy The total number of above properties that affect the reduction potential is _________ (Integer answer)

Q189·ChemistryNumericalJEE Main 2021

For the galvanic cell,

\mathrm{Zn(s)} + \mathrm{Cu}^{2+} (0.02\ \mathrm{M}) \rightarrow \mathrm{Zn}^{2+} (0.04\ \mathrm{M}) + \mathrm{Cu(s)}

,

E_{cell} =

______

\times 10^{-2}

V. (Nearest integer) [Use :

E^{0}_{\mathrm{Cu/Cu}^{2+}} = -0.34

V,

E^{0}_{\mathrm{Zn/Zn}^{2+}} = +0.76

V,

\frac{2.303\ RT}{F} = 0.059

V]

Q190·ChemistryNumericalJEE Main 2021

For the cell Cu(s) | Cu

^{2+}

(aq)(0.1M) ‖ Ag

^+

(aq)(0.01M) | Ag(s) The cell potential E

_1

= 0.3095V For the cell Cu(s) | Cu

^{2+}

(aq)(0.01M) ‖ Ag

^+

(aq)(0.001M) | Ag(s) The cell potential = __________×10

^{-2}

V. (Round off to the Nearest Integer). [Use :

\frac{2.303RT}{F}

= 0.059 ]

Q191·ChemistrySingle correctJEE Main 2021

The product obtained from the electrolytic oxidation of acidified sulphate solutions, is:

(A) $HO_3SOSO_3H$
(B) $HSO_4^-$
(C) $HO_2SOSO_2H$
(D) $HO_3SOOSO_3H$

Q192·ChemistryNumericalJEE Main 2021

When 10 ml of an aqueous solution of Fe

^{2+}

ions was titrated in the presence of dil H

_2

SO

_4

using diphenylamine indicator, 15 mL of 0.02 M solution of K

_2

Cr

_2

O

_7

was required to get the end point. The molarity of the solution containing Fe

^{2+}

ions is x

\times 10^{-2}

M. The value of x is___. (Nearest integer)

Q193·ChemistrySingle correctJEE Main 2021

The correct order of following 3d metal oxides, according to their oxidation numbers is: (a)

CrO_3

(b)

Fe_2O_3

(c)

MnO_2

(d)

V_2O_5

(e)

Cu_2O

(A)(a) > (d) > (c) > (b) > (e)
(B)(c) > (a) > (d) > (e) > (b)
(C)(d) > (a) > (b) > (c) > (e)
(D)(a) > (c) > (d) > (b) > (e)

Q194·ChemistryNumericalJEE Main 2021

Consider the cell at 25°C Zn | Zn

^{2+}

(aq), (1M) || Fe

^{3+}

(aq), Fe

^{2+}

(aq) | Pt(s) The fraction of total iron present as Fe

^{3+}

ion at the cell potential of 1.500V is x

\times 10^{-2}

. The value of x is ______. (Nearest integer) (Given:

E^{0}_{Fe^{3+}/Fe^{2+}}

= 0.77V,

E^{0}_{Zn^{2+}/Zn}

= −0.76V )

Q195·ChemistrySingle correctJEE Main 2021

Identify the process in which change in the oxidation state is five:

(A) $CrO_4^{2-}$ → $Cr^{3+}$
(B) $MnO_4^-$ → $Mn^{2+}$
(C) $Cr_2O_7^{2-}$ → $2Cr^{3+}$
(D) $C_2O_4^{2-}$ → $2CO_2$

Q196·ChemistryNumericalJEE Main 2021

Assume a cell with the following reaction

\mathrm{Cu_{(s)} + 2Ag^+ \left(1 \times 10^{-3}\,M\right) \rightarrow Cu^{2+} \left(0.250\,M\right) + 2Ag_{(s)}}

E_{\mathrm{cell}}^{\ominus}

= 2.97 V

E_{\mathrm{cell}}

for the above reaction is _____________ V. (Nearest integer) [ Given : log 2.5 = 0.3979, T = 298K]

Q197·ChemistryNumericalJEE Main 2021

Potassium chlorate is prepared by electrolysis of

\mathrm{KCl}

in basic solution as shown by following equation.

6\,\mathrm{OH}^- + \mathrm{Cl}^- \rightarrow \mathrm{ClO_3^-} + 3\,\mathrm{H_2O} + 6\,\mathrm{e}^-

A current of xA has to be passed for 10 h to produce 10.0 g of potassium chlorate. The value of

x

is ________. (Nearest Integer) (Molar mass of

\mathrm{KClO_3} = 122.6\ \mathrm{g\ mol^{-1}},\ \mathrm{F} = 96500\ \mathrm{C}

)

Q198·ChemistrySingle correctJEE Main 2021

The species given below that does NOT show disproportionation reaction is:

(A) $BrO^{-}$
(B) $BrO_{3}^{-}$
(C) $BrO_{2}^{-}$
(D) $BrO_{4}^{-}$

Q199·ChemistryNumericalJEE Main 2021

For the reaction 2Fe

^{3+}

(aq) + 2I

^{-}

(aq) → 2Fe

^{2+}

(aq) + I

_{2}

(s) the magnitude of the standard molar free energy change,

\Delta_{r}G^{\circ}_{m}

= – ______ kJ (Round off to the Nearest Integer). [

E^{\circ}_{Fe^{2+}/Fe(s)}

= −0.440 V;

E^{\circ}_{Fe^{3+}/Fe(s)}

= −0.036 V;

E^{\circ}_{I_{2}/2I^{-}}

= 0.539 V; F = 96500 C]

Q200·ChemistrySingle correctJEE Main 2021

The oxidation states of nitrogen in NO, NO

_{2}

, N

_{2}

O and NO

_{3}^{-}

are in the order of :

(A)NO $_{3}^{-}$ > NO $_{2}$ > NO > N $_{2}$ O
(B)NO $_{2}$ > NO $_{3}^{-}$ > NO > N $_{2}$ O
(C)N $_{2}$ O > NO $_{2}$ > NO > NO $_{3}^{-}$
(D)NO > NO $_{2}$ > N $_{2}$ O > NO $_{3}^{-}$

Q201·ChemistryNumericalJEE Main 2021

The molar conductivities at infinite dilution of barium chloride, sulphuric arid and hydrochloric acid are 280, 860 and 426 Scm

^{2}

mol

^{-1}

respectively. The molar conductivity at infinite dilution of barium sulphate is ________ S cm

^{2}

mol

^{-1}

(Round off to the Nearest Integer).

Q202·ChemistryNumericalJEE Main 2021

15 mL of aqueous solution of

\mathrm{Fe^{2+}}

in acidic medium completely reacted with 20 mL of 0.03 M aqueous

\mathrm{Cr_2O_7^{2-}}

. The molarity of the

\mathrm{Fe^{2+}}

solution is ________

\times 10^{-2}

M (Round off to the Nearest Integer).

Q203·ChemistryNumericalJEE Main 2021

A KCl solution of conductivity 0.14 S m

^{-1}

shows a resistance of 4.19

\Omega

in a conductivity cell. If the same cell is filled with an HCl solution, the resistance drops to 1.03

\Omega

. The conductivity of the HCl solution is ____

\times

10

^{-2}

S m

^{-1}

. (Round off to the Nearest Integer).

Q204·ChemistryNumericalJEE Main 2021

2 MnO

_{4}^{-}

+ b C

_{2}

O

_{4}^{2-}

+ c H

^{+}

→ x Mn

^{2+}

+ y CO

_{2}

+ z H

_{2}

O If the above equation is balanced with integer coefficients, the value of c is _______. (Round off to the Nearest Integer).

Q205·ChemistryNumericalJEE Main 2021

A 5.0 m mol dm

^{-3}

aqueous solution of KCl has a conductance of 0.55 mS when measured in a cell constant 1.3 cm

^{-1}

. The molar conductivity of this solution is _______ mSm

^{2}

mol

^{-1}

. (Round off to the Nearest Integer)

Q206·ChemistryNumericalJEE Main 2021

Emf of the following cell at 298 K in V is x

\times10^{-2}

.

Zn|Zn^{2+}

(0.1 M)

||Ag^+

(0.01 M)

|

Ag The value of x is ___________. (Rounded off to the nearest integer) [Given:

E^0_{Zn^{2+}/Zn}

= −0.76V;

E^0_{Ag^+/Ag}

= +0.80V;

\frac{2.303RT}{F}

= 0.059]

Q207·ChemistryNumericalJEE Main 2021

In mildly alkaline medium, thiosulphate ion is oxidized by

MnO_4^-

to "A". The oxidation state of sulphur in "A" is_________.

Q208·ChemistryNumericalJEE Main 2021

Consider the following reaction MnO

_4^{-}

+ 8H

^+

+ 5e

^-

→ Mn

^{+2}

+ 4H

_2

O, E° = 1.51 V. The quantity of electricity required in Faraday to reduce five moles of MnO

_4^{-}

is_____.

Q209·ChemistryNumericalJEE Main 2021

In basic medium CrO

_{4}^{2-}

oxidizes S

_{2}

O

_{3}^{2-}

to form SO

_{4}^{2-}

and itself changes into Cr(OH)

_{4}^{-}

. The volume of 0.154 M CrO

_{4}^{2-}

required to react with 40 mL of 0.25 M S

_{2}

O

_{3}^{2-}

is _______ mL. (Rounded-off to the nearest integer)

Q210·ChemistryNumericalJEE Main 2021

Copper reduces NO

_{3}

−into NO and NO2 depending upon the concentration of HNO3 in solution. (Assuming fixed [Cu

^{2+}

] and PNO=PNO2), the HNO3 concentration at which the thermodynamic tendency for reduction of NO

_{3}

− into NO and NO2 by copper is same is 10

^{x}

M. The value of 2x is ______. (Rounded-off to the nearest integer)

_{[Given :}

E

_{Cu}^{0}

2+

_{/}_{Cu}

=0.34V ,E

_{NO}^{0}_{3}

−

_{/}_{NO}

=0.96V ,E

_{NO}^{0}_{3}

−

_{/}_{NO}_{2}

=0.79V and at 298 K, RTF(2.303)=0.059]

_{]}

Q211·ChemistryNumericalJEE Main 2021

The reaction of sulphur in alkaline medium is given below:

\mathrm{S_{8(s)}} + a\,\mathrm{OH^-}_{(aq)} \longrightarrow b\,\mathrm{S^{2-}}_{(aq)} + c\,\mathrm{S_2O_3^{2-}}_{(aq)} + d\,\mathrm{H_2O}_{(\ell)}

The values of 'a' is __________. (Integer answer)

Q212·ChemistryNumericalJEE Main 2021

The magnitude of the change in oxidising power of the

MnO_{4}^{-}

/

Mn^{2+}

couple is x ×

10^{-4}

V, if the

H^{+}

concentration is decreased from 1M to

10^{-4}

M at 25ºC. (Assume concentration of

MnO_{4}^{-}

and

Mn^{2+}

to be same on change in

H^{+}

concentration). The value of x is ______. (Rounded off to the nearest integer)

\left[ Given : \frac{2303RT}{F} = 0.059 \right]

Q213·ChemistryIntegerJEE Advanced 2020

In the chemical reaction between stoichiometric quantities of

KMnO_{4}

and KI in weakly basic solution, what is the number of moles of

I_{2}

released for 4 moles of

KMnO_{4}

consumed ?

Q214·ChemistryNumericalJEE Advanced 2020

Consider a 70% efficient hydrogen-oxygen fuel cell working under standard conditions at 1 bar and 298 K. Its cell reaction is

H_2 (g) + \frac{1}{2} O_2(g) \rightarrow H_2O(\ell)

. The work derived from the cell on the consumption of

1.0 \times 10^{-3}

mol of

H_2(g)

is used to compress 1.00 mol of a monoatomic ideal gas in a thermally insulted container. What is the change in the temperature (in K) of the ideal gas ? The standard reduction potentials for the two half-cells are given below.

O_2(g) + 4\,H^+ (aq.) + 4e^- \rightarrow 2H_2O\,(\ell)

,

E^\circ = 1.23

V,

2H^+ (aq.) + 2e^- \rightarrow H_2(g)

,

E^\circ = 0.00

V. Use

F = 96500

C

mol^{-1}

,

R = 8.314

J

mol^{-1}K^{-1}

Q215·ChemistrySingle correctJEE Main 2020

For the given cell; Cu(s) | Cu

^{2+}

(C

_1

M) || Cu

^{2+}

(C

_2

M) | Cu(s) Change in Gibbs energy (ΔG) is negative, if

(A)C $_1$ = C $_2$
(B) $\frac{C_2 = C_1}{\sqrt{2}}$
(C)C $_1$ = 2C $_2$
(D)C $_2$ = $\sqrt{2}$ C $_1$

Q216·ChemistryNumericalJEE Main 2020

Potassium chlorate is prepared by the electrolysis of KCl in basic solution

6HO^- + Cl^- \rightarrow ClO_3^- + 3H_2O + 6e^-

If only 60% of the current is utilized in the reaction, the time (rounded to the nearest hour) required to produce 10 g of

KClO_3

using a current of 2A is ________________. (Given : F = 96,500 C mol

^{-1}

; molar mass of

KClO_3

= 122 g mol

^{-1}

)

Q217·ChemistryNumericalJEE Main 2020

The volume, in mL, of 0.02 M K

_2

Cr

_2

O

_7

solution required to react with 0.288 g of ferrous oxalate in acidic medium is __________. (Molar mass of Fe = 56 mol

^{-1}

)

Q218·ChemistryNumericalJEE Main 2020

An oxidation – reduction in which 3 electrons are transferred has a

\Delta G^0

of 17.37 kJ

mol^{-1}

at

25^0

C. The value of

E^0_{cell}

(in V is _____ ×

10^{-2}

) (1 F = 96,500 C

mol^{-1}

)

Q219·ChemistrySingle correctJEE Main 2020

The variation of molar conductivity with concentration of an electrolyte (X) in aqueous solution is shown in the given figure.

(A) $KNO_3$
(B) $CH_3COOH$
(C) $HCl$
(D) $NaCl$

Q220·ChemistryNumericalJEE Main 2020

At 20.0 mL solution containing 0.2 g impure H

_2

O

_2

reacts completely with 0.316 g of KMnO

_4

in acid solution. The purity of H

_2

O

_2

(in %) is _______________. (mol. wt. of H

_2

O

_2

= 34; mol. wt. of KMnO

_4

= 158)

Q221·ChemistrySingle correctJEE Main 2020

Identify the incorrect statement from the options below for the above cell:

(A)If $E_{ext} < 1.1$ V, Zn dissolves at anode and Cu deposits at cathode
(B)If $E_{ext} = 1.1$ V, no flow of e $^-$ or current occurs
(C)If $E_{ext} > 1.1$ V, Zn dissolves at Zn electrode and Cu deposits at Cu electrode
(D)If $E_{ext} > 1.1$ V, e $^-$ flows from Cu to Zn

Q222·ChemistrySingle correctJEE Main 2020

250 mL of a waste solution obtained from the workshop of a goldsmith contains 0.1 M

AgNO_3

and 0.1 M

AuCl

. The solution was electrolyzed at 2 V by passing a current of 1 A for 15 minutes. The metal/metals electrodeposited will be :

\left(E^{o}_{Ag^{+}/Ag} = 0.8\ V, E^{o}_{Au^{+}/Au} = 1.69\ V\right)

(A)silver and gold in equal mass proportion
(B)only silver
(C)only gold
(D)silver and gold in proportion to their atomic weights

Q223·ChemistryNumericalJEE Main 2020

Consider the following equations :

2\mathrm{Fe}^{2+} + \mathrm{H}_2\mathrm{O}_2 \rightarrow x\,\mathrm{A} + y\,\mathrm{B}

(in basic medium) (in acidic medium)

2\mathrm{MnO}_4^- + 6\mathrm{H}^+ + 5\mathrm{H}_2\mathrm{O}_2 \rightarrow x'\mathrm{C} + y'\mathrm{D} + z'\mathrm{E}

(in acidic medium) The sum of the stoichiometric coefficients x, y, x', y' and z' for products A, B, C, D and E, respectively, is ………..

Q224·ChemistryNumericalJEE Main 2020

An acidic solution of dichromate is electrolyzed for 8 minutes using 2A current. As per the following equation Cr

_{2}

O

_{7}^{2-}

+ 14H

^{+}

+ 6e

^{-}

→ 2Cr

^{3+}

+ 7H

_{2}

O. The amount of Cr

^{3+}

obtained was 0.104 g. The efficiency of the process (in %) is (Take: F = 96000 C, At. Mass of chromium = 52) ______.

Q225·ChemistryNumericalJEE Main 2020

The photoelectric current from Na (work function, w

_0

= 2.3 eV) is stopped by the output voltage of the cell Pt(s)/H

_2

(g, 1 bar) | HCl (aq., pH = 1) | AgCl(s) | Ag(s). The pH of aq. HCl required to stop the photoelectric current from K(w

_0

= 2.25 eV), all other conditions remaining the same, is __________

\times

10

^{-2}

(to the nearest integer). Given, 2.303

\frac{RT}{F}

= 0.06 V ; E

^0_{AgCl\,|\,Ag\,|\,Cl^-}

= 0.22 V

Q226·ChemistryNumericalJEE Main 2020

108 g of silver (molar mass 108 g mol

^{-1}

) is deposited at cathode from AgNO

_{3}

(aq) solution by a certain quantity of electricity. The volume (in L) of oxygen gas produced at 273 K and 1 bar pressure from water by the same quantity of electricity is_.

Q227·ChemistrySingle correctJEE Main 2020

Amongst the following, the form of water with the lowest ionic conductance at 298 K is :

(A)sea water
(B)distilled water
(C)saline water used for intravenous injection
(D)water from a well

Q228·ChemistrySingle correctJEE Main 2020

The compound that cannot act both as oxidising and reducing agent is:

(A)H $_2$ O $_2$
(B)H $_2$ SO $_3$
(C)HNO $_2$
(D)H $_3$ PO $_4$

Q229·ChemistryNumericalJEE Main 2020

For an electrochemical cell

Sn(s)|Sn^{2+}(aq, 1M)||Pb^{2+}(aq, 1M)|Pb(s)

the ratio

\dfrac{[Sn^{2+}]}{[Pb^{2+}]}

when this cell attains equilibrium is ____. (Given:

E^0_{Sn^{2+}|Sn} = -0.14V, E^0_{Pb^{2+}|Pb} = -0.13V, \dfrac{2.303RT}{F} = 0.06

)

Q230·ChemistrySingle correctJEE Main 2020

The redox reaction among the following is

(A)reaction of $\mathrm{[Co(H_2O)_6]Cl_3}$ with $\mathrm{AgNO_3}$
(B)combination of dinitrogen with dioxygen at 2000 K
(C)reaction of $\mathrm{H_2SO_4}$ with NaOH
(D)formation of ozone from atmospheric oxygen in the presence of sunlight

Q231·ChemistrySingle correctJEE Main 2020

Oxidation number of potassium in K

_2

O, K

_2

O

_2

and KO

_2

respectively is

(A)+1, +2 and +4
(B)+2, +1 and +½
(C)+1, +1 and +1
(D)+1, +4 and +2

Q232·ChemistrySingle correctJEE Main 2020

Given that the standard potential (E°) of Cu

^{2+}

/Cu and Cu

^{+}

/Cu are 0.34 V and 0.522 V respectively, the E° of Cu

^{2+}

/Cu

^{+}

is

(A)-0.158 V
(B)0.182 V
(C)+0.158 V
(D)-0.182 V

Q233·ChemistrySingle correctJEE Main 2020

The equation that is incorrect is

(A) $(\Lambda_m^0)_{NaBr} - (\Lambda_m^0)_{NaI} = (\Lambda_m^0)_{KBr} - (\Lambda_m^0)_{NaBr}$
(B) $(\Lambda_m^0)_{NaBr} - (\Lambda_m^0)_{NaCl} = (\Lambda_m^0)_{KBr} - (\Lambda_m^0)_{KCl}$
(C) $(\Lambda_m^0)_{H_2O} = (\Lambda_m^0)_{HCl} + (\Lambda_m^0)_{NaOH} - (\Lambda_m^0)_{NaCl}$
(D) $(\Lambda_m^0)_{KCl} - (\Lambda_m^0)_{NaCl} = (\Lambda_m^0)_{KBr} - (\Lambda_m^0)_{NaBr}$

Q234·ChemistryNumericalJEE Advanced 2019

The amount of water produced (in g) in the oxidation of 1 mole of rhombic sulphur by conc. HNO

_{3}

to a compound with the highest oxidation state of sulphur is______ (Given data : Molar mass of water = 18 g mol

^{-1}

)

Q235·ChemistrySingle correctJEE Main 2019

The decreasing order of electrical conductivity of the following aqueous solutions is: 0.1 M Formic acid (a) 0.1 M Acetic acid (b) 0.1 M Benzoic acid (c)

(A)a > c > b
(B)c > a > b
(C)c > b > a
(D)a > b > c

Q236·ChemistrySingle correctJEE Main 2019

Given : Co

^{3+}

e

^{-}

\longrightarrow

Co

^{2+}

; E° = 1.81 V Pb

^{4}

+2e

^{-}

\longrightarrow

Pb

^{2+}

; E° = +1.67 V Ce

^{4+}

+ e

^{-}

\longrightarrow

Ce

^{3+}

; E° +1.61 V Bi

^{3+}

+ 3e

^{-}

\longrightarrow

Bi ; E° = +0.20 V Oxidizing power of the species will increase in the order

(A)Ce $^{4+}$ < Pb $^{4+}$ < Bi $^{3+}$ < Co $^{3+}$
(B)Co $^{3+}$ < Pb $^{4+}$ < Ce $^{4+}$ < Bi $^{3+}$
(C)Bi $^{3+}$ < Ce $^{4+}$ < Pb $^{4+}$ < Co $^{3+}$
(D)Co $^{3+}$ < Ce $^{4+}$ < Bi $^{3+}$ < Pb $^{4+}$

Q237·ChemistrySingle correctJEE Main 2019

An example of a disproportionation reaction is :

(A) $2KMnO_4 \rightarrow K_2MnO_4 + MnO_2 + O_2$
(B) $2NaBr + Cl_2 \rightarrow 2naCl + Br_2$
(C) $2CuBr \rightarrow CuBr_2 + Cu$
(D) $2MnO_4^- + 10I^- + 16H^+ \rightarrow 2Mn^{2+} + 5I_2 + 8H_2O$

Q238·ChemistrySingle correctJEE Main 2019

Consider the statements S1 and S2: S1: Conductivity always increases with decrease in the concentration of electrolyte. S2: Molar conductivity always increases with decrease in the concentration of electrolyte. The correct option among the following is:

(A)S1 is wrong and S2 is correct
(B)Both S1 and S2 are wrong
(C)S1 is correct and S2 is wrong
(D)Both S1 and S2 are correct

Q239·ChemistrySingle correctJEE Main 2019

Which one of the following graphs between molar conductivity (Λ

_m

) versus

\sqrt{C}

is correct?

(A)(A)
(B)(B)
(C)(C)
(D)(D)

Q240·ChemistrySingle correctJEE Main 2019

A solution of Ni(NO

_3

)

_2

is electrolysed between platinum electrodes using 0.1 Faraday electricity. How many mole of Ni will be deposited at the cathode?

(A)0.20
(B)0.05
(C)0.10
(D)0.15

Q241·ChemistrySingle correctJEE Main 2019

The standard Gibbs energy for the given cell reaction in kJ

mol^{-1}

at 298 K is:

Zn(s) + Cu^{2+}(aq) \rightarrow Zn^{2+}(aq) + Cu(s), E^\circ = 2 V

at 298K [Faraday's constant F = 96500 C

mol^{-1}

]

(A)-192
(B)384
(C)-384
(D)192

Q242·ChemistrySingle correctJEE Main 2019

In order to oxidize a mixture of one mole of each of

FeC_2O_4

,

Fe_2(C_2O_4)_3

,

FeSO_4

and

Fe_2(SO_4)_3

in acidic medium, the number of moles of

KMnO_4

required is:

(A)1
(B)1.5
(C)2
(D)3

Q243·ChemistrySingle correctJEE Main 2019

Calculate the standard cell potential (in V) of the cell in which following reaction takes place:

Fe^{2}+(aq)+Ag^{+}(aq)\rightarrow Fe^{3+}(aq)+Ag(s)

Given that:

E^{0}_{Ag'/Ag}=xV

E^{0}_{Fe^{2+}/Fe}=yV

E^{0}_{Fe^{3+}/Fe}=zV

(A)x \u2212 z
(B)x + y \u2212 z
(C)x \u2212 y
(D)x + 2y \u2212 3z

Q244·ChemistrySingle correctJEE Main 2019

Given that

E^0_{O_2/H_2O} = +1.23V

;

E^0_{S_2O_8^{2-}/SO_4^{2-}} = 2.05V

;

E^0_{Br_2/Br^-} = +1.09V

;

E^0_{Au^{3+}/Au} = 1.4V

. The strongest oxidizing agent is:

(A) $O_2$
(B) $S_2O_8^{2-}$
(C) $Au^{3+}$
(D) $Br_2$

Q245·ChemistrySingle correctJEE Main 2019

The standard electrode potential

E^{\ominus}

and its temperature coefficient

\left(\dfrac{dE^{\ominus}}{dT}\right)

for a cell are 2 V and

-5\times10^{-4}

V

K^{-1}

at 300 K respectively. The cell reaction is :

Zn(s)+Cu^{2+}(aq)\rightleftharpoons Zn^{2+}(aq)+Cu(s)

Standard reaction enthalpy (

\Delta_rH^{\ominus}

)........

(A)-412.8
(B)-384.0
(C)1920
(D)206.4 kJ

Q246·ChemistrySingle correctJEE Main 2019

\wedge^{\circ}_{m}

for NaCl, HCl and NaA are 126.4, 425.9 and 100.5 S cm

^{2}

mol

^{-1}

, respectively. If the conductivity of 0.001 M HA is

5\times10^{-5}

S cm

^{-1}

, degree of dissociation of HA is :

(A)0.50
(B)0.25
(C)0.125
(D)0.75

Q247·ChemistrySingle correctJEE Main 2019

For the cell

Zn(s)|Zn^{2+}(aq)||M^{x+}(aq)|M(s)

, different half cells and their standard electrode potentials are given below: If

E^{0}_{Zn^{2+}/Zn} = -0.76

V, which cathode will given a maximum value of

E^{0}_{cell}

per electron transferred?

$M^{x+}(aq)/M(s)$	$Au^{3+}(aq)/Au(s)$	$Ag^{+}(aq)/Ag(s)$	$Fe^{3+}(aq)/Fe^{2+}(aq)$	$Fe^{2+}(aq)/Fe(s)$
$E^{\circ}_{M^{x+}/M}$ /(V)	1.40	0.80	0.77	-0.44

(A) $Ag^{+}/Ag$
(B) $Fe^{3+}/Fe^{2+}$
(C) $Au^{3+}/Au$
(D) $Fe^{2+}/Fe$

Q248·ChemistrySingle correctJEE Main 2019

Given the equilibrium constant:

K_{C}

of the reaction:

Cu(s) + 2Ag^{+}(aq) \rightarrow Cu^{2+}(aq) + 2Ag(s)

is

10 \times 10^{15}

, calculate the

E^{\theta}_{cell}

of the reaction of 298 K

\left[2.303\dfrac{RT}{F} \text{ at } 298K = 0.059V\right]

(A)0.04736 mV
(B)0.4736 mV
(C)0.4736 V
(D)0.04736 V

Q249·ChemistrySingle correctJEE Main 2019

Consider the following Zn

^{2+}

+ 2e

^{-}

\longrightarrow

Zn(s); E

^{o}

=

-0.76

V Ca

^{2+}

+ 2e

^{-}

\longrightarrow

Ca(s); E

^{o}

=

-2.87

V Mg

^{2+}

+ 2e

^{-}

\longrightarrow

Mg(s); E

^{o}

=

-2.36

V Ni

^{2+}

+ 2e

^{-}

\longrightarrow

Ni(s); E

^{o}

=

-0.25

V The reducing power of the metals increases in the order

(A)Ca < Zn < Mg < Ni
(B)Ni < Zn < Mg < Ca
(C)Zn < Mg < Ni < Ca
(D)Ca < Mg < Zn < Ni

Q250·ChemistrySingle correctJEE Main 2019

The anodic half-cell of lead-acid battery is recharged using electricity of 0.05 Faraday. The amount of PbSO

_{4}

electrolyzed in g during the process is: (Molar mass of PbSO

_{4}

= 303 g mol

^{-1}

)

(A)22.8
(B)15.2
(C)7.6
(D)11.4

Q251·ChemistrySingle correctJEE Main 2019

If the standard electrode potential for a cell is 2 V at 300 K, the equilibrium constant (K) for the reaction

Zn(s) + Cu^{2+}(aq) \rightleftharpoons Zn^{2+}(aq) + Cu(s)

At 300 K is approximately (R = 8 JK

^{-1}

mol

^{-1}

, F = 96000 C mol

^{-1}

)

(A) $e^{-80}$
(B) $e^{-160}$
(C) $e^{320}$
(D) $e^{160}$

Q252·ChemistryNumericalJEE Advanced 2018

Consider an electrochemical cell:

A(s) | A^{n+} (aq, 2 M) || B^{2n+} (aq, 1 M) | B(s)

. The value of

\Delta H^{\ominus}

for the cell reaction is twice that of

\Delta G^{\ominus}

at 300 K. If the emf of the cell is zero, the

\Delta S^{\ominus}

(in J

K^{-1}

mol^{-1}

) of the cell reaction per mole of B formed at 300 K is ____. (Given:

\ln(2) = 0.7

, R (universal gas constant) = 8.3 J

K^{-1}

mol^{-1}

.

H

,

S

and

G

are enthalpy, entropy and Gibbs energy, respectively.)

Q253·ChemistryNumericalJEE Advanced 2018

To measure the quantity of

MnCl_{2}

dissolved in an aqueous solution, it was completely converted to

KMnO_{4}

using the reaction,

MnCl_{2} + K_{2}S_{2}O_{8} + H_{2}O \rightarrow KMnO_{4} + H_{2}SO_{4} + HCl

(equation not balanced). Few drops of concentrated HCl were added to this solution and gently warmed. Further, oxalic acid (225 mg) was added in portions till the colour of the permanganate ion disappeared. The quantity of

MnCl_{2}

(in mg) present in the initial solution is ____. (Atomic weights in g

mol^{-1}

: Mn = 55, Cl = 35.5)

Q254·ChemistryNumericalJEE Advanced 2018

For the electrochemical cell,

Mg(s) \mid Mg^{2+} (aq, 1\ M) \parallel Cu^{2+} (aq, 1\ M) \mid Cu(s)

the standard emf of the cell is 2.70 V at 300 K. When the concentration of

Mg^{2+}

is changed to

x

M, the cell potential changes to 2.67 V at 300 K. The value of

x

is ___. (given,

\dfrac{F}{R} = 11500

K

V^{-1}

, where

F

is the Faraday constant and

R

is the gas constant,

\ln(10) = 2.30

)

Q255·ChemistryIntegerJEE Advanced 2017

The conductance of a 0.0015 M aqueous solution of a weak monobasic acid was determined by using a conductivity cell consisting of platinized Pt electrodes. The distance between the electrodes is 120 cm with an area of cross section of 1

cm^{2}

. The conductance of this solution was found to be

5 \times 10^{-7}

S. The pH of the solution is 4. The value of limiting molar conductivity

\left(\Lambda_{m}^{o}\right)

of this weak monobasic acid in aqueous solution is

Z \times 10^{2}

S

cm^{-1}

mol^{-1}

. The value of Z is

Q256·ChemistrySingle correctJEE Advanced 2017

For the following cell,

\mathrm{Zn}(s)\,|\,\mathrm{ZnSO_{4}}(aq)\,\|\,\mathrm{CuSO_{4}}(aq)\,|\,\mathrm{Cu}(s)

When the concentration of

\mathrm{Zn^{2+}}

is 10 times the concentration of

\mathrm{Cu^{2+}}

, the expression for

\Delta G

(in J mol

^{-1}

) is [F is Faraday constant; R is gas constant; T is temperature;

E^{0}(cell)

= 1.1 V]

(A) $1.1\,F$
(B) $2.303\,RT - 2.2\,F$
(C) $2.303\,RT + 1.1\,F$
(D) $-2.2\,F$

Q257·ChemistryIntegerJEE Advanced 2016

In neutral or faintly alkaline solution, 8 moles of permanganate anion quantitatively oxidize thiosulphate anions to produce

\mathbf{X}

moles of a sulphur containing product. The magnitude of

\mathbf{X}

is

Q258·ChemistrySingle correctJEE Advanced 2016

For the following electrochemical cell at 298 K,

Pt(s)\,|\,H_{2}(g, 1\ bar)\,|\,H^{+}(aq, 1\ M)\,||\,M^{4+}(aq), M^{2+}(aq)\,|\,Pt(s)

E_{cell} = 0.092

V when

\dfrac{[M^{2+}(aq)]}{[M^{4+}(aq)]} = 10^{x}

Given:

E^{0}_{M^{4+}/M^{2+}} = 0.151

V;

2.303\dfrac{RT}{F} = 0.059

V The value of

x

is

(A) $-2$
(B) $-1$
(C)1
(D)2

Q259·ChemistryIntegerJEE Advanced 2015

All the energy released from the reaction

\mathbf{X} \to \mathbf{Y}

,

\Delta_{r}G^{0} = -193

kJ mol

^{-1}

is used for oxidizing

\mathbf{M^{+}}

as

\mathbf{M^{+}} \to \mathbf{M^{3+}} + 2e^{-}

,

E^{0} = -0.25

V. Under standard conditions, the number of moles of

\mathbf{M^{+}}

oxidized when

\mathbf{one}

mole of

\mathbf{X}

is converted to

\mathbf{Y}

is [F = 96500 C mol

^{-1}

]

Q260·ChemistryIntegerJEE Advanced 2015

The molar conductivity of a solution of a weak acid HX (0.01 M) is 10 times smaller than the molar conductivity of a solution of a weak acid HY (0.10 M). If

\lambda^{0}_{\mathrm{X^{-}}} \approx \lambda^{0}_{\mathrm{Y^{-}}}

, the difference in their

\mathrm{p}K_{a}

values,

\mathrm{p}K_{a}(\mathrm{HX}) - \mathrm{p}K_{a}(\mathrm{HY})

, is (consider degree of ionization of both acids to be

\ll 1

)

Q261·ChemistryMultiple correctJEE Advanced 2014

In a galvanic cell, the salt bridge

(A)does not participate chemically in the cell reaction.
(B)stops the diffusion of ions from one electrode to another.
(C)is necessary for the occurrence of the cell reaction.
(D)ensures mixing of the two electrolytic solutions.

Q262·ChemistryMultiple correctJEE Advanced 2014

For the reaction:

I^- + ClO_3^- + H_2SO_4 \longrightarrow Cl^- + HSO_4^- + I_2

The correct statement(s) in the balanced equation is/are:

(A)Stoichiometric coefficient of $HSO_4^-$ is 6.
(B)Iodide is oxidized.
(C)Sulphur is reduced.
(D) $H_2O$ is one of the products.

Q263·ChemistryIntegerJEE Advanced 2014

Consider the following list of reagents: Acidified

K_2Cr_2O_7

, alkaline

KMnO_4

,

CuSO_4

,

H_2O_2

,

Cl_2

,

O_3

,

FeCl_3

,

HNO_3

and

Na_2S_2O_3

. The total number of reagents that can oxidise aqueous iodide to iodine is

Q264·ChemistrySingle correctJEE Advanced 2013

The standard reduction potential data at 25°C is given below:

E^{\circ}(\mathrm{Fe^{3+}}, \mathrm{Fe^{2+}}) = +0.77\ \mathrm{V};

E^{\circ}(\mathrm{Fe^{2+}}, \mathrm{Fe}) = -0.44\ \mathrm{V}

E^{\circ}(\mathrm{Cu^{2+}}, \mathrm{Cu}) = +0.34\ \mathrm{V};

E^{\circ}(\mathrm{Cu^{+}}, \mathrm{Cu}) = +0.52\ \mathrm{V}

E^{\circ}[\mathrm{O_2(g)} + 4\mathrm{H^{+}} + 4e^{-} \rightarrow 2\mathrm{H_2O}] = +1.23\ \mathrm{V};

E^{\circ}[\mathrm{O_2(g)} + 2\mathrm{H_2O} + 4e^{-} \rightarrow 4\mathrm{OH^{-}}] = +0.40\ \mathrm{V}

E^{\circ}(\mathrm{Cr^{3+}}, \mathrm{Cr}) = -0.74\ \mathrm{V};

E^{\circ}(\mathrm{Cr^{2+}}, \mathrm{Cr}) = -0.91\ \mathrm{V}

Match

E^{0}

of the redox pair in List – I with the values given in List – II and select the correct answer using the code given below the lists:

List – I	List – II
P. $E^{\circ}(\mathrm{Fe^{3+}}, \mathrm{Fe})$	1. $-0.18\ \mathrm{V}$
Q. $E^{\circ}(4\mathrm{H_2O} \rightleftharpoons 4\mathrm{H^{+}} + 4\mathrm{OH^{-}})$	2. $-0.4\ \mathrm{V}$
R. $E^{\circ}(\mathrm{Cu^{2+}} + \mathrm{Cu} \longrightarrow 2\mathrm{Cu^{+}})$	3. $-0.04\ \mathrm{V}$
S. $E^{\circ}(\mathrm{Cr^{3+}}, \mathrm{Cr^{2+}})$	4. $-0.83\ \mathrm{V}$

(A)P-4, Q-1, R-2, S-3
(B)P-2, Q-3, R-4, S-1
(C)P-1, Q-2, R-3, S-4
(D)P-3, Q-4, R-1, S-2

Q265·ChemistrySingle correctJEE Advanced 2013

An aqueous solution of X is added slowly to an aqueous solution of Y as shown in List – I. The variation in conductivity of these reactions in List – II. Match List – I with List – II and select the correct answer using the code given below the lists:

List – I	List – II
P. $(C_2H_5)_3N$ (X) + $CH_3COOH$ (Y)	1.Conductivity decreases and then increases
Q. $\mathrm{KI(0.1M)}$ (X) + $\mathrm{AgNO_3(0.01M)}$ (Y)	2.Conductivity decreases and then does not change much
R. $CH_3COOH$ (X) + $KOH$ (Y)	3.Conductivity increases and then does not change much
S. $NaOH$ (X) + $HI$ (Y)	4.Conductivity does not change much and then increases

(A)P-3, Q-4, R-2, S-1
(B)P-4, Q-3, R-2, S-1
(C)P-2, Q-3, R-4, S-1
(D)P-1, Q-4, R-3, S-2

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