How many questions from Some Basic Concepts in Chemistry appear in JEE?

Some Basic Concepts in Chemistry has appeared in 129 of the last 186 JEE Main and JEE Advanced papers — about 69% of them — contributing 163 questions in total across those papers.

Is Some Basic Concepts in Chemistry an important chapter for JEE?

Judged by how often it is actually tested, it appears in roughly 69% 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 Some Basic Concepts in Chemistry 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.

Some Basic Concepts in Chemistry JEE Previous Year Questions with Answers

Q1·ChemistrySingle correctJEE Main 2026

Match List-I (Mass of substance) with List-II (Number of atoms). Choose the correct answer from the options given below:

List-I (Mass of substance)	List-II (Number of atoms)
A.1.8 mg water	I. $2 \times 10^{-4} \times N_A$
B.9.8 mg sulphuric acid	II. $1.5 \times 10^{-4} \times N_A$
C.1.8 mg carbon	III. $3 \times 10^{-4} \times N_A$
D.5.85 mg salt (NaCl)	IV. $7 \times 10^{-4} \times N_A$

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

Q2·ChemistrySingle correctJEE Main 2026

Which of the following contain the same number of atoms ? (Given : Molar mass in g mol

^{-1}

of H, He, O and S are 1, 4, 16 and 32 respectively) A. 2 g of

\mathrm{O_{2}}

gas B. 4 g of

\mathrm{SO_{2}}

gas C. 1400 mL of

\mathrm{O_{2}}

at STP D. 0.05 L of He at STP E. 0.0625 mol of

\mathrm{H_{2}}

gas Choose the correct answer from the options given below :

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

Q3·ChemistrySingle correctJEE Main 2026

An oxide of iron contains 69.9% iron, its empirical formula, is: (Given: Molar mass of Fe and O are 56 and 16 g mol⁻¹ respectively.)

(A)FeO
(B)Fe₂O₃
(C)Fe₃O₄
(D)FeO₃

Q4·ChemistrySingle correctJEE Main 2026

What volume of hydrogen gas at STP would be liberated by action of 50 mL of H₂SO₄ of 50% purity (density = 1.3 g mL⁻¹) on 20 g of zinc ? Given : Molar mass of H, O, S, Zn are 1, 16, 32, 65 g mol⁻¹ respectively.

(A)5.824 L
(B)7.428 L
(C)6.892 L
(D)8.375 L

Q5·ChemistrySingle correctJEE Main 2026

How many grams of residue is obtained by heating 2.76 g of silver carbonate? (Given: Molar mass of C, O and Ag are 12, 16 and 108 g mol

^{-1}

respectively)

(A)1.08 g
(B)2.16 g
(C)3.24 g
(D)4.32 g

Q6·ChemistrySingle correctJEE Main 2026

The correct order of total number of atoms present in (A) 2 moles of cyclohexane (B) 684 g of sucrose (C) 90.8 L of dihydrogen at STP is:

(A) $C > A > B$
(B) $C > B > A$
(C) $B > C > A$
(D) $B > A > C$

Q7·ChemistrySingle correctJEE Main 2026

Number of moles and number of molecules in

1.4187

L of

SO_2

at STP respectively are:

(A) $0.1266; 3.812 \times 10^{22}$
(B) $0.0633; 3.812 \times 10^{22}$
(C) $0.1266; 7.6238 \times 10^{22}$
(D) $0.0633; 7.6238 \times 10^{22}$

Q8·ChemistrySingle correctJEE Main 2026

The mass of iron converted into

\mathrm{Fe_{3}O_{4}}

by the action of 18 g of steam is : (Given : Molar mass of H, O and Fe are 1, 16 and 56 g

\mathrm{mol^{-1}}

respectively) Assume iron is present in excess :

(A)2.1 g
(B)4.2 g
(C)21 g
(D)42 g

Q9·ChemistrySingle correctJEE Main 2026

The ratio of mass percentage (w/w) of C : H in a hydrocarbon is 12 : 1. It has two carbon atoms. The weight (in g) of

CO_2(g)

formed when 3.38 g of this hydrocarbon is completely burnt in oxygen is : (Given : Molar mass in g mol

^{-1}

C : 12, H : 1, O : 16)

(A)5.68
(B)11.44
(C)22.74
(D)17.05

Q10·ChemistrySingle correctJEE Main 2026

For the given reaction;

CaCO_3 + 2HC1 \rightarrow CaCl_2 + H_2O + CO_2

If 90 g

CaCO_3

is added to 300 mL of HCl which contains 38.55% HCl by mass and has density 1.13 g

mL^{-1}

, then which of the following option is correct? Given molar mass of H, Cl, Ca and O are 1, 35.5, 40 and 16 g

mol^{-1}

respectively.

(A)64.97 g of HCl remains unreacted
(B)32.85 g of $CaCO_3$ remains unreacted
(C)97.30 g of HCl reacted
(D)60.32 g of HCl reamains unreacted

Q11·ChemistryNumericalJEE Main 2026

x mg of pure HCl was used to make an aqueous solution. 25.0 mL of 0.1M Ba(OH)

_2

solution is used when the HCl solution was titrated against it. The numerical value of x is ______

\times 10^{-1}

. (Nearest integer) Given : Molar mass of HCl and Ba(OH)

_2

are 36.5 and 171.0 g mol

^{-1}

respectively.

Q12·ChemistrySingle correctJEE Main 2026

In the reaction, 2Al(s) + 6HCl(aq) → 2Al

^{3+}

(aq) + 6Cl

^{-}

(aq) + 3H

_2

(g)

(A)11.2 L H $_2$ (g) at STP is produced for every mole of HCl consumed.
(B)67.2 L H $_2$ (g) at STP is produced for every mole of Al that reacts.
(C)12 L HCl(aq) is consumed for every 6L H $_2$ (g) produced.
(D)33.6 L H $_2$ (g) is produced regardless of temperature and pressure for every mole of Al that reacts.

Q13·ChemistrySingle correctJEE Main 2026

A + 2B \rightarrow AB_2

36.0 g of 'A' (Molar mass : 60 g

mol^{-1}

) and 56.0 g of 'B' (Molar mass : 80 g

mol^{-1}

) are allowed to react. Which of the following statements are correct ? (A) 'A' is the limting reagent (B) 77.0 g of

AB_2

is formed (C) Molar mass of

AB_2

is 140 g

mol^{-1}

(D) 15.0 g of A is left unreacted after the completion of reaction. Choose the correct answer from the options given below :

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

Q14·ChemistrySingle correctJEE Main 2026

At T(K), 100 g of 98%

H_2SO_4

(w/w) aqueous solution is mixed with 100 g of 49%

H_2SO_4

(w/w) aqueous solution. What is the mole fraction of

H_2SO_4

in the resultant solution ? (Given : Atomic mass H = 1 u ; S = 32 u; O = 16 u) (Assume that temperature after mixing remains constant)

(A)0.9
(B)0.1
(C)0.337
(D)0.663

Q15·ChemistrySingle correctJEE Main 2026

Aqueous HCl reacts with

\text{MnO}_{2}\text{(s)}

to form

\text{MnCl}_{2}\text{(aq)}

,

\text{Cl}_{2}\text{(g)}

and

\text{H}_{2}\text{O}(l)

. What is the weight (in g) of

\text{Cl}_{2}

liberated when 8.7 g of

\text{MnO}_{2}\text{(s)}

is reacted with excess aqueous HCl solution ? (Given Molar mass in

\text{g mol}^{-1}

Mn = 55, Cl = 35.5, O = 16, H = 1)

(A)7.1
(B)71
(C)21.3
(D)14.2

Q16·ChemistrySingle correctJEE Main 2026

80 mL of a hydrocarbon on mixing with 264 mL of oxygen in a closed U-tube undergoes complete combustion. The residual gases after cooling to 273 K occupy 224 mL. When the system is treated with KOH solution, the volume decreases to 64 mL. The formula of the hydrocarbon is :

(A) $C_2H_4$
(B) $C_4H_{10}$
(C) $C_2H_2$
(D) $C_2H_6$

Q17·ChemistrySingle correctJEE Main 2026

14.0 g of calcium metal is allowed to react with excess HCl at 1.0 atm pressure and 273 K. Which of the following statements is incorrect ? [Given : Molar mass in g

mol^{-1}

of Ca–40, Cl–35.5,H–1]

(A)0.35 mol of $H_2$ gas is evolved.
(B)7.84 L of $H_2$ gas is evolved.
(C)33.3 of $CaCl_2$ is produced.
(D)The limiting reagent is calcium metal.

Q18·ChemistryIntegerJEE Main 2025

20 mL of sodium iodide solution gave 4.74 g silver iodide when treated with excess of silver nitrate solution. The molarity of the sodium iodide solution is ___ M. (Nearest Integer value). (Given: Na = 23, I = 127, Ag = 108, N = 14, O = 16 g mol

^{-1}

)

Q19·ChemistrySingle correctJEE Main 2025

At the sea level, the dry air mass percentage composition is given as nitrogen gas: 70.0, oxygen gas: 27.0 and argon gas: 3.0. If total pressure is 1.15 atm, then calculate the ratio of followings respectively: (i) partial pressure of nitrogen gas to partial pressure of oxygen gas (ii) partial pressure of oxygen gas to partial pressure of argon gas (Given: Molar mass of N, O and Ar are 14, 16, and 40 g mol

^{-1}

respectively)

(A)4.26, 19.3
(B)2.59, 11.85
(C)5.46, 17.8
(D)2.96, 11.2

Q20·ChemistryIntegerJEE Main 2025

Butane reacts with oxygen to produce carbon dioxide and water following the equation given below:

C_4H_{10}(g)+\dfrac{13}{2}O_2(g)\rightarrow 4CO_2(g)+5H_2O(l)

If 174.0 kg of butane is mixed with 320.0 kg of

O_2

, the volume of water formed in litres is __________. (Nearest integer) [Given: (a) Molar mass of C, H, O are 12, 1, 16 g mol

^{-1}

respectively, (b) Density of water = 1 g mL

^{-1}

]

Q21·ChemistryIntegerJEE Main 2025

Fortification of food with iron is done using

FeSO_4\cdot7H_2O

. The mass in grams of the

FeSO_4\cdot7H_2O

required to achieve 12 ppm of iron in 150 kg of wheat is ______ (Nearest integer). [Given: Molar mass of Fe, S and O respectively are 56, 32 and 16 g mol

^{-1}

]

Q22·ChemistryIntegerJEE Main 2025

The amount of calcium oxide produced on heating 150 kg limestone (75% pure) is ______ kg. (Nearest integer). (Given molar mass in g mol

^{-1}

of Ca:40, O:16, C:12)

Q23·ChemistrySingle correctJEE Main 2025

Compounds that should not be used as primary standards in titrimetric analysis are: A.

Na_2Cr_2O_7

B. Oxalic acid C. NaOH D.

FeSO_4\cdot 6H_2O

E. Sodium tetraborate Choose the most appropriate answer from the options given below:

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

Q24·ChemistrySingle correctJEE Main 2025

Mass of magnesium required to produce 220 mL of hydrogen gas at STP on reaction with excess of dil. HCl is: (Given: Molar mass of Mg is 24 g mol

^{-1}

)

(A)235.7 g
(B)0.24 mg
(C)236 mg
(D)2.444 g

Q25·ChemistryIntegerJEE Main 2025

X g of nitrobenzene on nitration gave 4.2 g of m-dinitrobenzene. X = __________ g. (nearest integer) [Given: molar mass (in g mol

^{-1}

) C: 12, H: 1, O: 16, N: 14]

Q26·ChemistrySingle correctJEE Main 2025

10 mL of 2 M NaOH solution is added to 20 mL of 1 M HCl solution kept in a beaker. Now, 10 mL of this mixture is poured into a volumetric flask of 100 mL containing 2 mole of HCl and made the volume upto the mark with distilled water. The solution in this flask is:

(A)0.2 M NaCl solution
(B)20 M HCl solution
(C)10 M HCl solution
(D)Neutral solution

Q27·ChemistrySingle correctJEE Main 2025

Among

10^{-9}

g (each) of the following elements, which one will have the highest number of atoms? Element : Pb, Po, Pr and Pt

(A)Po
(B)Pr
(C)Pb
(D)Pt

Q28·ChemistrySingle correctJEE Main 2025

40 mL of a mixture of

CH_3COOH

and HCl (aqueous solution) is titrated against 0.1 M NaOH solution conductometrically. Which of the following statement is correct?

(A)The concentration of $CH_3COOH$ in the original mixture is 0.005 M
(B)The concentration of HCl in the original mixture is 0.005 M
(C) $CH_3COOH$ is neutralised first followed by neutralisation of HCl
(D)Point 'C' indicates the complete neutralisation of HCl

Q29·ChemistrySingle correctJEE Main 2025

On complete combustion 1.0 g of an organic compound (X) gave 1.46 g of

CO_2

and 0.567 g of

H_2O

. The empirical formula mass of compound (X) is ______ g. (Given molar mass in g mol

^{-1}

: C:12, H:1, O:16)

(A)30
(B)45
(C)60
(D)15

Q30·ChemistrySingle correctJEE Main 2025

CaCO_3(s)+2HCl(aq)\to CaCl_2(aq)+CO_2(g)+H_2O(l)

. Consider the above reaction, what mass of

CaCl_2

will be formed if 250 mL of 0.76 M HCl reacts with 1000 g of

CaCO_3

? (Given: molar mass of Ca, C, O, H and Cl are 40, 12, 16, 1 and 35.5 g mol

^{-1}

, respectively)

(A)3.908 g
(B)2.636 g
(C)10.545 g
(D)5.272 g

Q31·ChemistrySingle correctJEE Main 2025

Choose the correct statements. (A) Weight of a substance is the amount of matter present in it. (B) Mass is the force exerted by gravity on an object. (C) Volume is the amount of space occupied by a substance. (D) Temperatures below

0^\circ

C are possible in Celsius scale, but in Kelvin scale negative temperature is not possible. (E) Precision refers to the closeness of various measurements for the same quantity.

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

Q32·ChemistryIntegerJEE Main 2025

Quantitative analysis of an organic compound (X) shows following % composition: C : 14.5% Cl : 64.46% H : 1.8%. (Empirical formula mass of the compound (X) is _______

\times 10^{-1}

) (Given molar mass in g mol

^{-1}

are C: 12, H: 1, O: 16, Cl: 35.5)

Q33·ChemistryIntegerJEE Main 2025

X g of benzoic acid on reaction with aq. NaHCO₃ release CO₂ that occupied 11.2 L volume at STP. X is _______ g.

Q34·ChemistryIntegerJEE Main 2025

Consider the following reaction occurring in the blast furnace.

Fe_3O_4(s)+4CO(g)\to 3Fe(l)+4CO_2(g)

. ‘x’ kg of iron is produced when

2.32\times10^3

kg Fe₃O₄ and

2.8\times10^2

kg CO are brought together in the furnace. The value of ‘x’ is _______ (nearest integer). [Given : Molar mass of Fe₃O₄ = 232 g mol⁻¹, Molar mass of CO = 28 g mol⁻¹, Molar mass of Fe = 56 g mol⁻¹]

Q35·ChemistrySingle correctJEE Main 2025

The elemental composition of a compound is 54.2% C, 9.2% H and 36.6% O. If the molar mass of the compound is 132 g mol

^{-1}

, the molecular formula of the compound is : [Given : The relative atomic mass of C : H : O = 12 : 1 : 16]

(A) $C_4H_9O_3$
(B) $C_6H_{12}O_6$
(C) $C_6H_{12}O_3$
(D) $C_4H_8O_2$

Q36·ChemistryIntegerJEE Main 2025

When 81.0 g of aluminium is allowed to react with 128.0 g of oxygen gas, the mass of aluminium oxide produced in grams is __________. (Nearest integer) Given: Molar mass of Al

=27.0

g mol

^{-1}

, Molar mass of O

=16.0

g mol

^{-1}

.

Q37·ChemistryIntegerJEE Main 2025

0.01 mole of an organic compound (X) containing 10% hydrogen, on complete combustion produced 0.9 g

H_2O

. Molar mass of (X) is __________ g mol

^{-1}

.

Q38·ChemistrySingle correctJEE Main 2025

2.8\times10^{-3}

mol of CO₂ is left after removing

10^{21}

molecules from its ‘x’ mg sample. The mass of CO₂ taken initially is (Given :

N_A=6.02\times10^{23}

mol

^{-1}

)

(A)196.2 mg
(B)98.3 mg
(C)150.4 mg
(D)48.2 mg

Q39·ChemistryIntegerJEE Main 2025

Some CO₂ gas was kept in a sealed container at a pressure of 1 atm and 273 K. This entire amount of CO₂ was later passed through an aqueous solution of Ca(OH)₂. The excess unreacted Ca(OH)₂ was neutralised with 40 mL of 0.1 M HCl. The CO₂ reacted with exactly half the initial amount of Ca(OH)₂ present. If the volume of the sealed container of CO₂ was x, then x is ______ cm³ (nearest integer).

Q40·ChemistryNumericalJEE Main 2024

When equal volume of 1M

HCl

and 1M

H_2SO_4

are separately neutralised by excess volume of 1M

NaOH

solution. X and y kJ of heat is liberated respectively. The value of y/x is _____.

Q41·ChemistrySingle correctJEE Main 2024

The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 'A'

\times10^{12}

hertz and that has a radiant intensity in that direction of

\dfrac{1}{'B'}

watt per steradian. 'A' and 'B' are respectively:

(A)540 and $\dfrac{1}{683}$
(B)540 and 683
(C)450 and $\dfrac{1}{683}$
(D)450 and 683

Q42·ChemistrySingle correctJEE Main 2024

Combustion of glucose

(C_6H_{12}O_6)

produces

CO_2

and water. The amount of oxygen (in g) required for the complete combustion of

900\,g

of glucose is: [Molar mass of glucose in

g\,mol^{-1}=180

]

(A) $480$
(B) $960$
(C) $800$
(D) $32$

Q43·ChemistrySingle correctJEE Main 2024

An organic compound has 42.1% carbon, 6.4% hydrogen and the remainder oxygen. If its molecular weight is 342, then its molecular formula is:

(A) $\text{C}_{11}\text{H}_{18}\text{O}_{12}$
(B) $\text{C}_{12}\text{H}_{20}\text{O}_{12}$
(C) $\text{C}_{14}\text{H}_{20}\text{O}_{10}$
(D) $\text{C}_{12}\text{H}_{22}\text{O}_{11}$

Q44·ChemistrySingle correctJEE Main 2024

The number of moles of methane required to produce 11 g of

\text{CO}_2

(g) after complete combustion is: (Given molar mass of methane = 16 g mol

^{-1}

)

(A)0.75
(B)0.25
(C)0.35
(D)0.5

Q45·ChemistrySingle correctJEE Main 2024

The incorrect postulates of Dalton's atomic theory are: (A) Atoms of different elements differ in mass. (B) Matter consists of divisible atoms. (C) Compounds are formed when atoms of different elements combine in a fixed ratio. (D) All the atoms of a given element have different properties including mass. (E) Chemical reactions involve reorganisation of atoms. Choose the correct answer from the options given below:

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

Q46·ChemistrySingle correctJEE Main 2024

The Molarity (M) of an aqueous solution containing

5.85\,g

of NaCl in

500\,mL

water is: (Given: Molar Mass Na:

23

and Cl:

35.5\,g\,mol^{-1}

)

(A) $20$
(B) $0.2$
(C) $2$
(D) $4$

Q47·ChemistrySingle correctJEE Main 2024

Choose the Incorrect Statement about Dalton's Atomic Theory:

(A)Compounds are formed when atoms of different elements combine in any ratio
(B)All the atoms of a given element have identical properties including identical mass
(C)Matter consists of indivisible atoms
(D)Chemical reactions involve reorganization of atoms

Q48·ChemistrySingle correctJEE Main 2024

Lassaigne's test is used for detection of:

(A)Nitrogen and Sulphur only
(B)Nitrogen, Sulphur and Phosphorous Only
(C)Phosphorous and halogens only
(D)Nitrogen, Sulphur, phosphorous and halogens

Q49·ChemistryNumericalJEE Main 2024

10 mL of gaseous hydrocarbon on combustion gives 40 mL of

\text{CO}_2(g)

and 50 mL of water vapour. Total number of carbon and hydrogen atoms in the hydrocarbon is __________.

Q50·ChemistrySingle correctJEE Main 2024

Given below are two statements: Statement (I): Potassium hydrogen phthalate is a primary standard for standardisation of sodium hydroxide solution. Statement (II): In this titration phenolphthalein can be used as indicator. 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 correct
(B)Statement I is correct but Statement II is incorrect
(C)Statement I is incorrect but Statement II is correct
(D)Both Statement I and Statement II are incorrect

Q51·ChemistryNumericalJEE Main 2024

Following Kjeldahl's method, 1g of organic compound released ammonia, that neutralised 10 mL of 2M

\text{H}_2\text{SO}_4

. The percentage of nitrogen in the compound is __________ %.

Q52·ChemistryNumericalJEE Main 2024

Consider the following reaction:

3PbCl_2+2(NH_4)_3PO_4\to Pb_3(PO_4)_2+6NH_4Cl

. If

72

mmol of

PbCl_2

is mixed with

50

mmol of

(NH_4)_3PO_4

, then amount of

Pb_3(PO_4)_2

formed is ___ mmol. (nearest integer)

Q53·ChemistryNumericalJEE Main 2024

The molarity of 1 L orthophosphoric acid (

H_3PO_4

) having 70% purity by weight (specific gravity 1.54 g cm

^{-3}

) is ______ M. (Molar mass of

H_3PO_4=98

g mol

^{-1}

)

Q54·ChemistrySingle correctJEE Main 2024

A sample of CaCO

_3

and MgCO

_3

weighed 2.21 g is ignited to constant weight of 1.152 g. The composition of mixture is: (Given molar mass in g mol

^{-1}

CaCO

_3

:100, MgCO

_3

:84)

(A)1.187 g CaCO $_3$ + 1.023 g MgCO $_3$
(B)1.023 g CaCO $_3$ + 1.023 g MgCO $_3$
(C)1.187 g CaCO $_3$ + 1.187 g MgCO $_3$
(D)1.023 g CaCO $_3$ + 1.187 g MgCO $_3$

Q55·ChemistryNumericalJEE Main 2024

Number of moles of methane required to produce 22 g

CO_{2(g)}

after combustion is

x\times10^{-2}

moles. The value of x is ______.

Q56·ChemistryNumericalJEE Main 2024

The mass of sodium acetate

(CH_3COONa)

required to prepare

250\,mL

of

0.35\,M

aqueous solution is ___ g. (Molar mass of

CH_3COONa

is

82.02\,g\,mol^{-1}

)

Q57·ChemistryNumericalJEE Main 2024

0.05\,cm

thick coating of silver is deposited on a plate of

0.05\,m^2

area. The number of silver atoms deposited on plate are ___

\times10^{23}

. (At mass Ag

=108

,

d=7.9\,g\,cm^{-3}

)

Q58·ChemistrySingle correctJEE Main 2024

If a substance 'A' dissolves in solution of a mixture of 'B' and 'C' with their respective number of moles as

n_A

,

n_B

and

n_C

, mole fraction of C in the solution is:

(A) $\dfrac{n_C}{n_A\times n_B\times n_C}$
(B) $\dfrac{n_C}{n_A+n_B+n_C}$
(C) $\dfrac{n_C}{n_A-n_B-n_C}$
(D) $\dfrac{n_B}{n_A+n_B}$

Q59·ChemistryNumericalJEE Main 2024

A solution of

H_2SO_4

is 31.4%

H_2SO_4

by mass and has a density of 1.25 g/mL. The molarity of the

H_2SO_4

solution is ______ M (nearest integer) [Given molar mass of

H_2SO_4=98

g mol

^{-1}

]

Q60·ChemistryNumericalJEE Main 2024

If 50 mL of 0.5 M oxalic acid is required to neutralise 25 mL of NaOH solution, the amount of NaOH in 50 mL of given NaOH solution is ___ g.

Q61·ChemistrySingle correctJEE Main 2024

IUPAC name of following compound (P) is:

(A)1-Ethyl-5,5-dimethylcyclohexane
(B)3-Ethyl-1,1-dimethylcyclohexane
(C)1-Ethyl-3,3-dimethylcyclohexane
(D)1,1-Dimethyl-3-ethylcyclohexane

Q62·ChemistryNumericalJEE Main 2024

9.3 g of aniline is subjected to reaction with excess of acetic anhydride to prepare acetanilide. The mass of acetanilide produced if the reaction is 100% completed is __________

\times10^{-1}

g. (Given molar mass in g mol

^{-1}

N : 14, O : 16, C : 12, H : 1).

Q63·ChemistrySingle correctJEE Main 2024

Cyclohexene is __________ type of an organic compound.

(A)Benzenoid aromatic
(B)Benzenoid non-aromatic
(C)Acyclic
(D)Alicyclic

Q64·ChemistryNumericalJEE Main 2024

Mass of methane required to produce 22 g of

\text{CO}_2

after complete combustion is __________ g. (Given Molar mass in g mol

^{-1}

:

C=12.0

;

H=1.0

;

O=16.0

)

Q65·ChemistryNumericalJEE Main 2023

1 g of a carbonate (

M_2CO_3

) on treatment with excess HCl produces 0.01 mol of

CO_2

. The molar mass of

M_2CO_3

is ____ g mol

^{-1}

. (Nearest integer)

Q66·ChemistryNumericalJEE Main 2023

20\,mL

of calcium hydroxide was consumed when it was reacted with

10\,mL

of unknown solution of

H_{2}SO_{4}

. Also

20\,mL

standard solution of

0.5\,M\,HCl

containing

2

drops of phenolphthalein was titrated with calcium hydroxide the mixture showed pink colour when burette displayed the value of

35.5\,mL

, whereas the burette showed

25.5\,mL

initially. The concentration of

H_{2}SO_{4}

is _____

M

(Nearest integer).

Q67·ChemistrySingle correctJEE Main 2023

The number of molecules and moles in 2.8375 litres of O

_2

at STP are respectively

(A)1.752 $\times$ 10 $^{22}$ and 0.250 mol
(B)1.505 $\times$ 10 $^{23}$ and 0.250 mol
(C)7.527 $\times$ 10 $^{22}$ and 0.125 mol
(D)7.527 $\times$ 10 $^{23}$ and 0.125 mol

Q68·ChemistrySingle correctJEE Main 2023

A metal chloride contains 55.0% of chlorine by weight. 100 mL vapours of the metal chloride at STP weigh 0.57 g. The molecular formula of the metal chloride is (Given: Atomic mass of chlorine is 35.5u)

(A)MCl $_2$
(B)MCl $_4$
(C)MCl $_3$
(D)MCl

Q69·ChemistryNumericalJEE Main 2023

A solution of sugar is obtained by mixing 200 g of its 25% solution and 500 g of its 40% solution (both by mass). The mass percentage of the resulting sugar solution is __________. (Nearest integer)

Q70·ChemistryNumericalJEE Main 2023

The volume of hydrogen liberated at STP by treating 2.4 g of magnesium with excess of hydrochloric acid is ____

\times10^{-2}

L. Given: Molar volume of gas is 22.4 L at STP; molar mass of magnesium is 24 g mol

^{-1}

.

Q71·ChemistrySingle correctJEE Main 2023

The number of molecules and moles in 2.8375 litres of O

_2

at STP are respectively

(A)1.752 $\times$ 10 $^{22}$ and 0.250 mol
(B)1.505 $\times$ 10 $^{23}$ and 0.250 mol
(C)7.527 $\times$ 10 $^{22}$ and 0.125 mol
(D)7.527 $\times$ 10 $^{23}$ and 0.125 mol

Q72·ChemistryAssertion & ReasonJEE Main 2023

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A:

3.1500

g of hydrated oxalic acid dissolved in water to make

250.0

mL solution will result in

0.1

M oxalic acid solution. Reason R: Molar mass of hydrated oxalic acid is

126

g mol

^{-1}

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

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

Q73·ChemistrySingle correctJEE Main 2023

Match List I (amount of a gas) with List II (its corresponding property). Choose the correct answer from the options given below:

List I	List II
A. $16$ g of $\text{CH}_4(g)$	I.Weighs $28$ g
B. $1$ g of $\text{H}_2(g)$	II. $60.2\times10^{23}$ electrons
C. $1$ mole of $\text{N}_2(g)$	III.Weighs $32$ g
D. $0.5$ mol of $\text{SO}_2(g)$	IV.Occupies $11.4$ L volume at STP

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

Q74·ChemistrySingle correctJEE Main 2023

Which of the following have the same number of significant figures? A.

0.00253

B.

1.0003

C.

15.0

D.

163

. Choose the correct answer from the options given below.

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

Q75·ChemistrySingle correctJEE Main 2023

The volume of 0.02 M aqueous HBr required to neutralize 10.0 mL of 0.01 M aqueous

Ba(OH)_2

(Assume complete neutralization) is

(A)2.5 mL
(B)5.0 mL
(C)10.0 mL
(D)7.5 mL

Q76·ChemistryNumericalJEE Main 2023

If

5

moles of

BaCl_2

is mixed with

2

moles of

Na_3PO_4

, the maximum number of moles of

Ba_3(PO_4)_2

formed is _____. (Nearest integer)

Q77·ChemistryNumericalJEE Main 2023

Zinc reacts with hydrochloric acid to give hydrogen and zinc chloride. The volume of hydrogen gas produced at STP from the reaction of

11.5

g of zinc with excess HCl is ___ L. (Nearest integer) (Given : Molar mass of Zn is

65.4

g

\,mol^{-1}

and Molar volume of

H_2

at STP is

22.7

L.)

Q78·ChemistryNumericalJEE Main 2023

Assume carbon burns according to following equation:

2C_{(s)}+O_{2(g)}\rightarrow 2CO(g)

. When 12 g carbon is burnt in 48 g of oxygen, the volume of carbon monoxide produced is _________

\times10^{-1}

L at STP (nearest integer) [Given: Assume CO as ideal gas, Mass of C is 12 g mol

^{-1}

, Mass of O is 16 g mol

^{-1}

and molar volume of an ideal gas at STP is 22.7 L mol

^{-1}

]

Q79·ChemistryNumericalJEE Main 2023

A

300

mL bottle of soft drink has

0.2

M CO

_2

dissolved in it. Assuming CO

_2

behaves as an ideal gas, the volume of the dissolved CO

_2

at STP is _________ mL. (Nearest integer) Given: At STP, molar volume of an ideal gas is

22.7

L mol

^{-1}

Q80·ChemistryNumericalJEE Main 2023

The volume of HCl, containing

73\,g\,L^{-1}

, required to completely neutralise NaOH obtained by reacting

0.69\,g

of metallic sodium with water, is _____ mL. (Nearest Integer) (Given: molar Masses of

Na,\,Cl,\,O,\,H

are

23,\,35.5,\,16

and

1\,g\,mol^{-1}

respectively)

Q81·ChemistryNumericalJEE Main 2023

Number of hydrogen atoms per molecule of a hydrocarbon A having 85.8% carbon is (Given: Molar mass of A

= 84

g mol

^{-1}

)

Q82·ChemistryNumericalJEE Main 2023

28.0 L of

CO_2

is produced on complete combustion of 16.8 L gaseous mixture of ethene and methane at

25^\circ C

and 1 atm. Heat evolved during the combustion process is _____ kJ. Given :

\Delta H_c(CH_4) = -900

kJ mol

^{-1}

\Delta H_c(C_2H_4) = -1400

kJ mol

^{-1}

Q83·ChemistryNumericalJEE Main 2023

The density of a monobasic strong acid (molar mass 24.2 g/mol) is 1.21 kg/L. The volume of its solution required for the complete neutralization of 25 mL of 0.24 M NaOH is _______

\times10^{-2}

mL (nearest integer).

Q84·ChemistryNumericalJEE Main 2023

5 g of NaOH was dissolved in deionized water to prepare a 450 mL stock solution. What volume (in mL) of this solution would be required to prepare 500 mL of 0.1 M solution? Given: Molar Mass of Na, O and H is 23, 16 and 1 g mol

^{-1}

respectively.

Q85·ChemistryMultiple correctJEE Advanced 2022

To check the principle of multiple proportions, a series of pure binary compounds

\left(\mathrm{P_mQ_n}\right)

were analyzed and their composition is tabulated below. The correct option(s) is(are) Compound | Weight % of P | Weight % of Q 1 | 50 | 50 2 | 44.4 | 55.6 3 | 40 | 60

(A)If empirical formula of compound $\mathbf{3}$ is $\mathrm{P_3Q_4}$ , then the empirical formula of compound $\mathbf{2}$ is $\mathrm{P_3Q_5}$ .
(B)If empirical formula of compound $\mathbf{3}$ is $\mathrm{P_3Q_2}$ , and atomic weight of element P is 20, then the atomic weight of Q is 45.
(C)If empirical formula of compound $\mathbf{2}$ is PQ, then the empirical formula of compound $\mathbf{1}$ is $\mathrm{P_5Q_4}$ .
(D)If atomic weight of P and Q are 70 and 35, respectively, then the empirical formula of compound $\mathbf{1}$ is $\mathrm{P_2Q}$ .

Q86·ChemistrySingle correctJEE Main 2022

N_{2(g)}

+

3H_{2(g)}

⇌

2NH_{3(g)}

20 g 5 g Consider the above reaction, the limiting reagent of the reaction and number of moles of

NH_{3}

formed respectively are:

(A) $H_{2}$ , 1.42 moles
(B) $H_{2}$ , 0.71 moles
(C) $N_{2}$ , 1.42 moles
(D) $N_{2}$ , 0.71 moles

Q87·ChemistrySingle correctJEE Main 2022

Consider the reaction 4HNO

_{3}

(l) + 3KCl(s) → Cl

_{2}

(g) + NOCl(g) + 2H

_{2}

O(g) + 3KNO

_{3}

(s) The amount of HNO

_{3}

required to produce 110.0 g of KNO

_{3}

is : (Given : Atomic masses of H, O, N and K are 1, 16, 14 and 39, respectively.)

(A)32.2 g
(B)69.4 g
(C)91.5 g
(D)162.5 g

Q88·ChemistryNumericalJEE Main 2022

In the given reaction, X + Y + 3Z ⇌ XYZ

_3

if one mole of each of X and Y with 0.05 mol of Z gives compound XYZ

_3

. (Given : Atomic masses of X, Y and Z are 10, 20 and 30 amu, respectively). The yield of XYZ

_3

is __________ g. (Nearest integer)

Q89·ChemistryNumericalJEE Main 2022

2L of 0.2 M

\mathrm{H_2SO_4}

is reacted with 2L of 0.1 M NaOH solution, the molarity of the resulting product

\mathrm{Na_2SO_4}

in the solution is _____ millimolar. (Nearest integer).

Q90·ChemistryNumericalJEE Main 2022

In the following reaction The % yield for reaction I is 60% and that of reaction II is 50%. The overall yield of the complete reaction is ___% [nearest integer]

Q91·ChemistryNumericalJEE Main 2022

The normality of H

_{2}

SO

_{4}

in the solution obtained on mixing 100 mL of 0.1 M H

_{2}

SO

_{4}

with 50 mL of 0.1 M NaOH is________×10

^{-1}

N. (Nearest Integer)

Q92·ChemistrySingle correctJEE Main 2022

Hemoglobin contains 0.34% of iron by mass. The number of Fe atoms in 3.3 g of hemoglobin is : (Given : Atomic mass of Fe is 56 u,

N_{A}

in 6.022 ×

10^{23}

mol^{-1}

)

(A)1.21 × $10^{5}$
(B)12.0 × $10^{16}$
(C)1.21 × $10^{20}$
(D)3.4 × $10^{22}$

Q93·ChemistryNumericalJEE Main 2022

Chlorophyll extracted from the crushed green leaves was dissolved in water to make 2 L solution of Mg of concentration 48 ppm. The number of atoms of Mg in this solution is x × 10

^{20}

atoms. The value of x is_________. (Nearest Integer) (Given : Atomic mass of Mg is 24 g mol

^{-1}

, N

_A

= 6.02 × 10

^{23}

mol

^{-1}

)

Q94·ChemistryNumericalJEE Main 2022

When 800 mL of 0.5 M nitric acid is heated in a beaker, its volume is reduced to half and 11.5 g of nitric acid is evaporated. The molarity of the remaining nitric acid solution is x × 10

^{-2}

M. (Nearest Integer) (Molar mass of nitric acid is 63 g mol

^{-1}

)

Q95·ChemistrySingle correctJEE Main 2022

SO_{2}Cl_{2}

on reaction with excess of water results into acidic mixture

SO_{2}Cl_{2} + 2H_{2}O \rightarrow H_{2}SO_{4} + 2HCl

16 moles of NaOH is required for the complete neutralisation of the resultant acidic mixture. The number of moles of

SO_{2}Cl_{2}

used is :

(A)16
(B)8
(C)4
(D)2

Q96·ChemistrySingle correctJEE Main 2022

Production of iron in blast furnace follows the following equation

Fe_3O_4(s) + 4CO(g) \rightarrow 3Fe(l) + 4CO_2(g)

when 4.640 kg of

Fe_3O_4

and 2.520 kg of CO are allowed to react then the amount of iron (in g) produced is : [Given : Molar Atomic mass (g

mol^{-1}

): Fe = 56 Molar Atomic mass (g

mol^{-1}

) : O = 16 Molar Atomic mass (g

mol^{-1}

): = C = 12

(A)1400
(B)2200
(C)3360
(D)4200

Q97·ChemistrySingle correctJEE Main 2022

Using the rules for significant figures, the correct answer for the expression

\frac{0.02858 \times 0.112}{0.5702}

will be:

(A)0.005613
(B)0.00561
(C)0.0056
(D)0.006

Q98·ChemistrySingle correctJEE Main 2022

Compound A contains 8.7% Hydrogen, 74% Carbon and 17.3% Nitrogen. The molecular formula of the compound is, Given : Atomic masses of C, H and N are 12, 1 and 14 amu respectively. The molar mass of the compound A is 162 g mol

^{-1}

.

(A)C $_4$ H $_6$ N $_2$
(B)C $_2$ H $_3$ N
(C)C $_5$ H $_7$ N
(D)C $_{10}$ H $_{14}$ N $_2$

Q99·ChemistryNumericalJEE Main 2022

116 g of a substance upon dissociation reaction, yields 7.5 g of hydrogen, 60g of oxygen and 48.5 g of carbon. Given that the atomic masses of H, O and C are 1, 16 and 12 respectively. The data agrees with how many formulae of the following? (A) CH

_3

COOH (B) HCHO (C) CH

_3

OOCH

_3

(D) CH

_3

CHO

Q100·ChemistryNumericalJEE Main 2022

Two elements A and B which form 0.15 moles of

A_{2}B

and

AB_{3}

type compounds. If both

A_{2}B

and

AB_{3}

weigh equally, then the atomic weight of A is _____ times of atomic weight of B.

Q101·ChemistrySingle correctJEE Main 2022

A commercially sold conc. HCl is 35% HCl by mass. If the density of this commercial acid is 1.46 g/mL, the molarity of this solution is : (Atomic mass : Cl = 35.5 amu, H = 1 amu)

(A)10.2 M
(B)12.5 M
(C)14.0 M
(D)18.2 M

Q102·ChemistryNumericalJEE Main 2022

CNG is an important transportation fuel. When 100 g CNG is mixed with 208 oxygen in vehicles, it leads to the formation of

CO_2

and

H_2O

and produces large quantity of heat during this combustion, then the amount of carbon dioxide, produced in grams is_________. [nearest integer] [Assume CNG to be methane]

Q103·ChemistrySingle correctJEE Main 2022

An evacuated glass vessel weighs 40.0 g when empty, 135.0 g when filled with a liquid of density 0.95 g

mL^{-1}

and 40.5 g when filled with an ideal gas at 0.82 atm at 250 K. The molar mass of the gas in g

mol^{-1}

is : (Given : R = 0.082 L atm

K^{-1}

mol^{-1}

)

(A)35
(B)50
(C)75
(D)125

Q104·ChemistryNumericalJEE Main 2022

The moles of methane required to produce 81 g of water after complete combustion is ______ ×

10^{-2}

mol. [nearest integer]

Q105·ChemistryNumericalJEE Main 2022

A rigid nitrogen tank stored inside a laboratory has a pressure of 30 atm at 06:00 am when the temperature is 27

^\circ

C. At 03:00 pm, when the temperature is 45

^\circ

C, the pressure in the tank will be ____________atm. [nearest integer]

Q106·ChemistryNumericalJEE Main 2022

1 L aqueous solution of

H_2SO_4

contains 0.02 m mol

H_2SO_4

. 50% of this solution is diluted with deionized water to give 1 L solution (A). In solution (A), 0.01 m mol of

H_2SO_4

are added. Total m mols of

H_2SO_4

in the final solution is ___________ ×

10^{3}

m mols.

Q107·ChemistryNumericalJEE Main 2022

A protein 'A' contains 0.30% of glycine (molecular weight 75). The minimum molar mass of the protein 'A' is________

\times

10

^3

g mol

^{-1}

[nearest integer]

Q108·ChemistryNumericalJEE Main 2022

The neutralization occurs when 10 mL of 0.1 M acid 'A' is allowed to react with 30 mL of 0.05 M base M(OH)

_2

. The basicity of the acid 'A' is______. [M is a metal]

Q109·ChemistryNumericalJEE Main 2022

The number of N atoms is 681 g of

C_7H_5N_3O_6

is x ×

10^{21}

. The value of x is ______ (

N_A

= 6.02 ×

10^{23}

mol^{-1}

) (Nearest Integer)

Q110·ChemistryNumericalJEE Main 2022

At 300 K, a sample of 3.0 g of gas A occupies the same volume as 0.2 g of hydrogen at 200 K at the same pressure. The molar mass of gas A is____ g mol

^{-1}

(nearest integer) Assume that the behaviour of gases as ideal. (Given: The molar mass of hydrogen (H

_2

) gas is 2.0 g mol

^{-1}

)

Q111·ChemistrySingle correctJEE Main 2022

120 of an organic compound that contains only carbon and hydrogen gives 330g of CO

_2

and 270g of water on complete combustion. The percentage of carbon and hydrogen, respectively are.

(A)25 and 75
(B)40 and 60
(C)60 and 40
(D)75 and 25

Q112·ChemistrySingle correctJEE Main 2022

If a rocket runs on a fuel (C

_{15}

H

_{30}

) and liquid oxygen, the weight of oxygen required and CO

_2

released for every litre of fuel respectively are: (Given: density of the fuel is 0.756 g/mL)

(A)1188 g and 1296 g
(B)2376 g and 2592 g
(C)2592g and 2376 g
(D)3429 g and 3142 g

Q113·ChemistryNumericalJEE Advanced 2021

Reaction of x g of Sn with HCl quantitatively produced a salt. Entire amount of the salt reacted with y g of nitrobenzene in the presence of required amount of HCl to produce 1.29 g of an organic salt (quantitatively). (Use Molar masses (in g mol

^{-1}

) of H, C, N, O, Cl and Sn as 1, 12, 14, 16, 35 and 119, respectively). The value of

\mathbf{x}

is ______.

Q114·ChemistryNumericalJEE Advanced 2021

Reaction of x g of Sn with HCl quantitatively produced a salt. Entire amount of the salt reacted with y g of nitrobenzene in the presence of required amount of HCl to produce 1.29 g of an organic salt (quantitatively). (Use Molar masses (in g mol

^{-1}

) of H, C, N, O, Cl and Sn as 1, 12, 14, 16, 35 and 119, respectively). The value of

\mathbf{y}

is ______.

Q115·ChemistryNumericalJEE Main 2021

If 80 g of copper sulphate CuSO

_{4}

·5H

_{2}

O is dissolved in deionised water to make 5 L of solution. The concentration of the copper sulphate solution is x × 10

^{-3}

mol L

^{-1}

. The value of x is ______ . [Atomic masses Cu : 63.54 u, S : 32 u, O : 16 u, H : 1 u]

Q116·ChemistryNumericalJEE Main 2021

The number of atoms in 8 g of sodium is x × 10

^{23}

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

_{A}

= 6.02 × 10

^{23}

mol

^{-1}

Atomic mass of Na = 23.0 u]

Q117·ChemistryNumericalJEE Main 2021

The molarity of the solution prepared by dissolving 6.3 g of oxalic acid (

\mathrm{H_2C_2O_4.2H_2O}

) in 250 mL of water in mol L

^{-1}

is x

\times

10

^{-2}

. The value of x is ____. (Nearest integer) [Atomic mass : H : 1.0, C : 12.0, O : 16.0]

Q118·ChemistryNumericalJEE Main 2021

Sodium oxide reacts with water to produce sodium hydroxide. 20.0 g of sodium oxide is dissolved in 500 mL of water. Neglecting the change in volume, the concentration of the resulting NaOH solution is ___________

\times

10

^{-1}

M. (Nearest integer) [Atomic mass : Na = 23.0, O = 16.0, H = 1.0]

Q119·ChemistryNumericalJEE Main 2021

100 g of propane is completely reacted with 1000 g of oxygen. The mole fraction of carbon dioxide in the resulting mixture is x × 10

^{-2}

. The value of x is _____ . (Nearest integer) [Atomic weight : H = 1.008; C = 12.00; O = 16.00]

Q120·ChemistryNumericalJEE Main 2021

100 mL of

\mathrm{Na_3PO_4}

solution contains 3.45 g of sodium. The molarity of the solution is ______

\times 10^{-2}

mol L

^{-1}

. (Nearest integer) [Atomic Masses - Na : 23.0 u, O : 16.0 u, P : 31.0 u]

Q121·ChemistryNumericalJEE Main 2021

10.0 ml of 0.05 M KMnO

_4

solution was consumed in a titration with 10.0 mL of given oxalic acid dehydrate solution. The strength of given oxalic acid solution is ___×10

^{-2}

g/ L (Round off to the Nearest Integer).

Q122·ChemistryNumericalJEE Main 2021

The density of NaOH solution is 1.2 gm cm

^{-3}

. The molality of this solution is _________m. (Round off to the Nearest integer) [ Use : Atomic masses : Na 23.0u O: 16.0 u H:1.0 u Density of

H_2

O: 1.0g cm

^{-3}

]

Q123·ChemistryNumericalJEE Main 2021

The number of significant figure in 0.00340 is______________.

Q124·ChemistryNumericalJEE Main 2021

Consider the complete combustion of butane, the amount of butane utilized to produce 72.0 g of water is ___________

\times 10^{-1}

g, (in nearest integer)

Q125·ChemistryNumericalJEE Main 2021

If the concentration of glucose

(\mathrm{C_6H_{12}O_6})

in blood is 0.72 g L

^{-1}

, the molarity of glucose in blood is __________

\times 10^{-3}

M. (Nearest integer) (Given : Atomic mass of C = 12, H = 1, O = 16u )

Q126·ChemistryNumericalJEE Main 2021

Methylation of 10g of benzene give 9.2g of toluene. Calculate the percentage yield of toluene __________. (Nearest integer)

Q127·ChemistryNumericalJEE Main 2021

An average person needs abut 10000 KJ energy per day.The amount of glucose (molar mass = 180.0 g mol

^{-1}

) needed to meet this energy requirement is____________ g, (Nearest integer) (Use :

\Delta_c

H (glucose) =

-2700

kJ mol

^{-1}

)

Q128·ChemistryNumericalJEE Main 2021

4g equimolar mixture of

\mathrm{NaOH}

and

\mathrm{Na_2CO_3}

contains

x

g of

\mathrm{NaOH}

and

y

g of

\mathrm{Na_2CO_3}

. The value of x is __________ g. (Nearest Integer)

Q129·ChemistryNumericalJEE Main 2021

250 mL of 0.5 M NaOH was added to 500 mL of 1 M HCl. The number of unreacted HCl molecules in the solution after complete reaction is____________

\times 10^{21}

(Nearest integer)

\left(N_A = 6.022 \times 10^{23}\right)

Q130·ChemistryNumericalJEE Main 2021

Complete combustion of 3 g of ethane gives x × 10

^{22}

molecules of water. The value of x is ______. (Round off to the Nearest Integer). [Use : N

_{A}

= 6.023 × 10

^{23}

; Atomic masses in u : C : 12.0 ; O : 16.0 ; H : 1.0]

Q131·ChemistryNumericalJEE Main 2021

10.0 ml of Na

_{2}

CO

_{3}

solution is titrated against 0.2 M HCl solution. The following titre values were obtained in 5 readings. 4.8 ml, 4.9 ml, 5.0 ml, 5.0 ml and 5.0 ml Based on these readings, and convention of titrimetric estimation of concentration of Na

_{2}

CO

_{3}

solution is ________ mM. (Round off to the Nearest integer)

Q132·ChemistryNumericalJEE Main 2021

Consider the above reaction where 6.1 g of benzoic acid is used to get 7.8 g of m-bromo benzoic acid. The percentage yield of the product is _____ . (Round off to the Nearest integer) [Given : Atomic masses : C = 12.0u, H : 1.0u, O : 16.0u, Br = 80.0 u]

Q133·ChemistryNumericalJEE Main 2021

______ grams of 3-Hydroxy propanal (MW=74) must be dehydrated to produce 7.8 g of acrolein (MW = 56) (C

_{3}

H

_{4}

O) if the percentage yield is 64. (Round off to the Nearest Integer). [Given : Atomic masses : C : 12.0 u, H : 1.0 u, O : 16.0 u]

Q134·ChemistryNumericalJEE Main 2021

In the above reaction, 3.9 g of benzene on nitration gives 4.92 g of nitrobenzene. The percentage yield of nitrobenzene in the above reaction is ________ %. (Round off to the Nearest Integer). (Given atomic mass : C : 12.0 u, H : 1.0u, O : 16.0 u, N : 14.0 u)

Q135·ChemistryNumericalJEE Main 2021

When 35 mL of 0.15 M lead nitrate solution is mixed with 20 mL of 0.12 M chromic sulphate solution, ________ × 10

^{-5}

moles of lead sulphate precipitate out. (Round off to the Nearest Integer).

Q136·ChemistryNumericalJEE Main 2021

The number of significant figures in 50000.020 × 10

^{-3}

is _______.

Q137·ChemistryNumericalJEE Main 2021

The

NaNO_3

weighed out to make 50 mL of an aqueous solution containing 70.0 mg

Na^+

per mL is_________g. (Rounded off to the nearest integer) [Given: Atomic weight in g

mol^{-1}

. Na: 23; N: 14; O : 16]

Q138·ChemistryNumericalJEE Main 2021

0.4g mixture of NaOH, Na

_{2}

CO

_{3}

and some inert impurities was first titrated with

\frac{N}{10}

HCl using phenolphthalein as an indicator, 17.5 mL of HCl was required at the end point. After this methyl orange was added and titrated. 1.5 mL of same HCl was required for the next end point. The weight percentage of Na

_{2}

CO

_{3}

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

Q139·ChemistryNumericalJEE Main 2021

Consider titration of NaOH solution versus 1.25 M oxalic acid solution. At the end point following burette readings were obtained. (i) 4.5 ml. (ii) 4.5 ml. (iii) 4.4 ml. (iv) 4.4 ml (v) 4.4 ml If the volume of oxalic acid taken was 10.0 ml. then the molarity of the NaOH solution is ____M. (Rounded-off to the nearest integer)

Q140·ChemistryNumericalJEE Main 2021

The formula of a gaseous hydrocarbon which requires 6 times of its own volume of

O_{2}

for complete oxidation and produces 4 times its own volume of

CO_{2}

is

C_{x}H_{y}

. The value of y is …………

Q141·ChemistryNumericalJEE Main 2021

4.5 g of compound A (MW = 90) was used to make 250 mL of its aqueous solution. The molarity of the solution in M is

x \times 10^{-1}

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

Q142·ChemistryNumericalJEE Advanced 2020

Aluminium reacts with sulfuric acid to form aluminium sulfate and hydrogen. What is the volume of hydrogen gas in liters (L) produced at 300 K and 1.0 atm pressure, when 5.4 g of aluminium and 50.0 mL of 5.0 M sulfuric acid are combined for the reaction ? (Use molar mass of aluminium as 27.0 g

mol^{-1}

,

R = 0.082

atm L

mol^{-1}\,K^{-1}

)

Q143·ChemistrySingle correctJEE Main 2020

The average molar mass of chlorine is 35.5 g mol

^{-1}

. The ratio of

^{35}

Cl to

^{37}

Cl in naturally occurring chlorine is close to:

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

Q144·ChemistryNumericalJEE Main 2020

The minimum number of moles of

O_2

required for complete combustion of 1 mole of propane and 2 moles of butane is ___

Q145·ChemistryNumericalJEE Main 2020

The mass of ammonia in grams produced when 2.8 kg of dinitrogen quantitatively reacts with 1 kg of dihydrogen is ___________.

Q146·ChemistryNumericalJEE Main 2020

A 100 mL solution was made by adding 1.43 g of Na

_2

CO

_3

.xH

_2

O. The normality of the solution is 0.1 N. The value of x is ……….. (The atomic mass of Na is 23 g/mol)

Q147·ChemistryNumericalJEE Main 2020

6.023

\times 10^{22}

molecules are present in 10 g of a substance 'x'. The molarity of a solution containing 5 g of substance 'x' in 2 L solution is ______

\times 10^{-3}

.

Q148·ChemistryNumericalJEE Main 2020

10.30 mg of O

_2

is dissolved into a liter of sea water of density 1.03 g/mL. The concentration of O

_2

in ppm is________________.

Q149·ChemistryNumericalJEE Main 2020

The molarity of HNO

_{3}

in a sample which has density 1.4 g/mL and mass percentage of 63% is (Molecular Weight of HNO

_{3}

= 63)

Q150·ChemistrySingle correctJEE Main 2020

5 g of zinc is treated separately with an excess of (a) dilute hydrochloric acid and (b) aqueous sodium hydroxide. The ratio of the volumes of H

_2

evolved in these two reactions is : -

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

Q151·ChemistryNumericalJEE Main 2020

Ferrous sulphate heptahydrate is used to fortify foods with iron. The amount (in grams) of the salt required to achieve 10 ppm of iron in 100 kg of wheat is ________ Atomic weight : Fe = 55.85; S = 32.00; O = 16.00

Q152·ChemistrySingle correctJEE Main 2020

Amongst the following statements, that which was not proposed by Dalton was

(A)matter consists of invisible atoms
(B)when gases combine or reproduced in a chemical reaction they do so in a simple ratio by volume provided all gases are at the same temperature & pressure
(C)chemical reactions involve reorganisation of atoms. These are neither created nor destroyed in a chemical reaction
(D)All the atoms of a given element have identical properties including identical mass. Atoms of different elements differ in mass

Q153·ChemistrySingle correctJEE Main 2020

The ammonia(

NH_3

) released on quantitative reaction of 0.6 g urea (

NH_2CONH_2

) with sodium hydroxide(NaOH) can be neutralized by

(A)100 mL of 0.1 N HCl
(B)100 mL of 0.2 N HCl
(C)200 mL of 0.2 N HCl
(D)200 mL of 0.4 N HCl

Q154·ChemistrySingle correctJEE Main 2019

25 g of an unknown hydrocarbon upon burning produces 88 g of CO

_{2}

and 9 g of H

_{2}

O. This unknown hydrocarbon contains.

(A)24g of carbon and 1 g of hydrogen
(B)22g of carbon and 3 g of hydrogen
(C)18g of carbon and 7 g of hydrogen
(D)20g of carbon and 5 g of hydrogen

Q155·ChemistrySingle correctJEE Main 2019

5 moles of AB

_2

weigh

125 \times 10^{-3}

kg and 10 moles of A

_2

B

_2

weigh

300 \times 10^{-3}

kg. The molar mass of A(M

_A

) and molar mass of B(M

_B

) in kg mol

^{-1}

are :

(A) $M_A = 50 \times 10^{-3}$ and $M_B = 25 \times 10^{-3}$
(B) $M_A = 10 \times 10^{-3}$ and $M_B = 5 \times 10^{-3}$
(C) $M_A = 5 \times 10^{-3}$ and $M_B = 10 \times 10^{-3}$
(D) $M_A = 25 \times 10^{-3}$ and $M_B = 50 \times 10^{-3}$

Q156·ChemistrySingle correctJEE Main 2019

The minimum amount of O

_2

(g) consumed per gram of reactant is for the reaction : (Given atomic mass : Fe = 56, O = 16, Mg = 24, P = 31, C = 12, H = 1)

(A)C $_3$ H $_8$ (g) + 5O $_2$ (g) → 3 CO $_2$ (g) + 4 H $_2$ O( $l$ )
(B)P $_4$ (s) + 5O $_2$ (g) → P $_4$ O $_{10}$ (s)
(C)4Fe(s) + 3O $_2$ (g) → 2 Fe $_2$ O $_3$ (s)
(D)2 Mg(s) + O $_2$ (g) → 2 MgO(s)

Q157·ChemistrySingle correctJEE Main 2019

At 300 K and 1 atmospheric pressure, 10 mL of a hydrocarbon required 55 mL of O

_2

for complete combustion, and 40 mL of CO

_2

is formed. The formula of the hydrocarbon is:

(A)C $_4$ H $_{10}$
(B)C $_4$ H $_6$
(C)C $_4$ H $_7$ Cl
(D)C $_4$ H $_8$

Q158·ChemistrySingle correctJEE Main 2019

For a reaction,

N_2(g) + 3H_2(g) \rightarrow 2NH_3(g)

; identify dihydrogen (

H_2

) as a limiting reagent in the following reaction mixtures.

(A)14g of $N_2$ + 4g of $H_2$
(B)28g of $N_2$ + 6g of $H_2$
(C)56g of $N_2$ + 10g of $H_2$
(D)35g of $N_2$ + 8g of $H_2$

Q159·ChemistrySingle correctJEE Main 2019

The percentage composition of carbon by mole in methane is:

(A)80%
(B)20%
(C)75%
(D)25%

Q160·ChemistrySingle correctJEE Main 2019

A 10 g effervescent tablet containing sodium bicarbonate and oxalic acid releases 0.25 ml of

CO_2

at T = 298.15 K and p = 1 bar. If molar volume of

CO_2

is 25.0 L under such condition, what is the percentage of sodium bicarbonate in each tablet? [Molar mass of

NaHCO_3

= 84 g mol

^{-1}

]

(A)0.84
(B)33.6
(C)16.8
(D)8.4

Q161·ChemistrySingle correctJEE Main 2019

For the following reaction the mass of water produced from 445 g of C

_{57}

H

_{110}

O

_6

is

2C_{57}H_{110}O_6(s) + 163O_2(g) \longrightarrow 114CO_2(g) + 110H_2O(l)

(A)490 g
(B)445 g
(C)495 g
(D)890 g

Q162·ChemistryNumericalJEE Advanced 2018

The ammonia prepared by treating ammonium sulphate with calcium hydroxide is completely used by

NiCl_{2}.6H_{2}O

to form a stable coordination compound. Assume that both the reactions are 100% complete. If 1584 g of ammonium sulphate and 952 g of

NiCl_{2}.6H_{2}O

are used in the preparation, the combined weight (in grams) of gypsum and the nickel-ammonia coordination compound thus produced is ___. (Atomic weights in g

mol^{-1}

: H = 1, N = 14, O = 16, S = 32, Cl = 35.5, Ca = 40, Ni = 59)

Q163·ChemistryIntegerJEE Advanced 2014

If the value of Avogadro number is

6.023 \times 10^{23} \text{ mol}^{-1}

and the value of Boltzmann constant is

1.380 \times 10^{-23} \text{JK}^{-1}

, then the number of significant digits in the calculated value of the universal gas constant is

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