How many questions from Atomic Structure appear in JEE?

Atomic Structure has appeared in 161 of the last 186 JEE Main and JEE Advanced papers — about 87% of them — contributing 182 questions in total across those papers.

Is Atomic Structure an important chapter for JEE?

Judged by how often it is actually tested, it appears in roughly 87% 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 Atomic Structure 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.

Atomic Structure JEE Previous Year Questions with Answers

Q1·ChemistryNumericalJEE Advanced 2026

X^{a+}

and

Y^{b+}

are hydrogen-like species. The wavelength of light absorbed during the transition between the states with principal quantum numbers

n = 1

and

n = 2

of

X^{a+}

is

\lambda

. The wavelength of light absorbed during the transition between the states with principal quantum numbers

n = 2

and

n = 4

of

Y^{b+}

is

9\lambda

. The lowest possible value of

(a + b)

is ____.

Q2·ChemistryMultiple correctJEE Advanced 2026

The 2s and the 2p orbital energies of hydrogen atom are

E_{2s}(\mathrm{H})

and

E_{2p}(\mathrm{H})

, respectively. The 2s and the 2p orbital energies of lithium atom are

E_{2s}(\mathrm{Li})

and

E_{2p}(\mathrm{Li})

, respectively. The correct option(s) about the orbital energies is(are)

(A) $E_{2s}(\mathrm{Li}) < E_{2p}(\mathrm{Li})$
(B) $E_{2s}(\mathrm{H}) = E_{2p}(\mathrm{H})$
(C) $E_{2p}(\mathrm{H}) < E_{2s}(\mathrm{Li})$
(D) $E_{2s}(\mathrm{H}) > E_{2s}(\mathrm{Li})$

Q3·ChemistryNumericalJEE Main 2026

Consider two radiations of wavelengths 1.

\lambda_1 = 2000

Å 2.

\lambda_2 = 6000

Å The ratio of the energies of these two radiations

\left(\frac{E_1}{E_2}\right)

is __________ (Nearest integer).

Q4·ChemistrySingle correctJEE Main 2026

The Bohr radius of a hydrogen like species is 70.53 pm. The species and the stationary state

(n)

are respectively (Given : Hydrogen atom Bohr radius is 52.9 pm)

(A) $\mathrm{Li^{2+}}$ , 3
(B) $\mathrm{He^{+}}$ , 3
(C) $\mathrm{He^{+}}$ , 2
(D) $\mathrm{Li^{2+}}$ , 2

Q5·ChemistrySingle correctJEE Main 2026

If shortest wavelength of hydrogen atom in Lyman series is

x

, then longest wavelength in Balmer series of He⁺ is:

(A) $\frac{9x}{5}$
(B) $\frac{36x}{5}$
(C) $\frac{x}{4}$
(D) $\frac{5x}{9}$

Q6·ChemistrySingle correctJEE Main 2026

Match the LIST-I (Orbital) with LIST-II (Radial nodes and nodal plane) Choose the correct answer from the options given below:

List-I (Orbital)	List-II (Radial nodes and nodal plane)
A.2s	I.1 Radial node + two nodal planes
B.3s	II.1 Radial node + one nodal plane
C.3p	III.2 Radial nodes + No nodal plane
D.4d	IV.1 Radial node + No nodal plane

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

Q7·ChemistrySingle correctJEE Main 2026

Identify the correct statements from the following: A. Heisenberg uncertainty principle is applicable to electrons. B. The size of

2p_x

orbital is less than the size of

3p_x

orbital. C. The energy of

2s

orbital of H atom is equal to the energy of

2s

orbital of Li. D. The electronic configuration of Cr is

[\mathrm{Ar}]3d^5 4s^1

Choose the correct answer from the options given below:

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

Q8·ChemistrySingle correctJEE Main 2026

Which of the following statement(s) is/are true ? A. If two orbitals have the same value of (n + l), the orbital with lower value of n will have lower energy. B. Energies of the orbitals in the same subshell increase with increase in atomic number. C. The size of

2p_x

orbital is less than the size of

3p_x

orbital. D. Among 5f, 6s, 4d, 5p and 5d orbitals, none of the orbitals have 2 radial nodes. Choose the correct answer from the options given below :

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

Q9·ChemistrySingle correctJEE Main 2026

Arrange the following atomic orbitals of multi electron atoms in order of increasing energy. A.

n = 3, l = 2, m = +1

B.

n = 4, l = 0, m = 0

C.

n = 6, l = 1, m = 0

D.

n = 5, l = 1, m = +1

E.

n = 2, l = 1, m = +1

Choose the correct answer from the options given below:

(A) $C < D < B < A < E$
(B) $B < A < E < C < D$
(C) $E < C < D < B < A$
(D) $E < B < A < D < C$

Q10·ChemistrySingle correctJEE Main 2026

What is the ratio of wave number of first line (lowest energy line) of Balmer series of H atomic spectrum to first line of its Brackett series?

(A) $5 : 1$
(B) $5 : 0.81$
(C) $5 : 1.75$
(D) $5 : 27$

Q11·ChemistrySingle correctJEE Main 2026

Which of the following is correct set of 4 quantum numbers of

19^{th}

electron in Chromium (Atomic number

= 24

) in accordance with Aufbau principle?

(A) $n = 3, l = 2, m = +2, s = +\frac{1}{2}$
(B) $n = 3, l = 2, m = -2, s = +\frac{1}{2}$
(C) $n = 4, l = 1, m = 0, s = +\frac{1}{2}$
(D) $n = 4, l = 0, m = 0, s = +\frac{1}{2}$

Q12·ChemistrySingle correctJEE Main 2026

The species having identical radii according to the Bohr's theory are: A.

H

(first orbit) B.

He^{+}

(first orbit) C.

He^{+}

(Second orbit) D.

Li^{2+}

(first orbit) E.

Be^{3+}

(Second orbit) Choose the correct answer from the options given below:

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

Q13·ChemistryNumericalJEE Main 2026

The surface of sodium metal is irradiated with radiation of wavelength

x

nm. The kinetic energy of ejected electrons is

2.8 \times 10^{-20}

J. The work function of sodium is 2.3 eV. The value of

x

is _______

\times 10^2

nm. (Nearest integer) (Given:

h = 6.6 \times 10^{-34}

J s; 1 eV

= 1.6 \times 10^{-19}

J;

c = 3.0 \times 10^8

m s

^{-1}

)

Q14·ChemistrySingle correctJEE Main 2026

What is the energy (in J

\mathrm{atom^{-1}}

) required for the following process?

\mathrm{Li^{2+}(g)} \rightarrow \mathrm{Li^{3+}(g)} + e^{-}

(Take the ionization energy for the H atom in the ground state as

2.18 \times 10^{-18}

J

\mathrm{atom^{-1}}

)

(A) $8.72 \times 10^{-18}$
(B) $1.962 \times 10^{-18}$
(C) $1.962 \times 10^{-17}$
(D) $6.54 \times 10^{-17}$

Q15·ChemistryNumericalJEE Main 2026

Two positively charged particles

m_1

and

m_2

have been accelerated across the same potential difference of 200 keV as shown below. [Given mass of

m_1

= 1 amu and

m_2

= 4 amu] The deBroglie wavelength of

m_1

will be x times of

m_2

. The value of x is ________. (nearest integer)

Q16·ChemistrySingle correctJEE Main 2026

Figure 1. electron probability density for 2s orbital Figure 2. wave function for 2s orbital Which of the following point in Figure 2 most accurately represents the nodal surface as shown in Figure 1 ?

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

Q17·ChemistrySingle correctJEE Main 2026

The wave numbers of three spectral lines of H atom are considered. Identify the set of spectral lines belonging to Balmer series. (R = Rydberg constant)

(A) $\frac{5R}{36}, \frac{3R}{16}, \frac{21R}{100}$
(B) $\frac{5R}{36}, \frac{8R}{9}, \frac{15R}{16}$
(C) $\frac{7R}{144}, \frac{3R}{16}, \frac{16R}{255}$
(D) $\frac{3R}{4}, \frac{3R}{16}, \frac{7R}{144}$

Q18·ChemistrySingle correctJEE Main 2026

The wavelength of photon 'A' is 400 nm. The frequency of photon 'B' is

10^{16}s^{-1}

. The wave number of photon 'C' is

10^4

cm^{-1}

. The correct order of energy of these photons is :

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

Q19·ChemistrySingle correctJEE Main 2026

The wavelength of spectral line obtained in the spectrum of

\text{LI}^{2+}

ion, when the transition takes place between two levels whose sum is 4 and difference is 2, is

(A) $2.28 \times 10^{-7}$ cm
(B) $2.28 \times 10^{-6}$ cm
(C) $1.14 \times 10^{-7}$ cm
(D) $1.14 \times 10^{-6}$ cm

Q20·ChemistryNumericalJEE Main 2026

The hydrogen spectrum consists of several spectral lines in Lyman series (

\mathrm{L_1}

,

\mathrm{L_2}

,

\mathrm{L_3}

....;

\mathrm{L_1}

has lowest energy among Lyman series). Similarly it consists of several spectral lines in Balmer series (

\mathrm{B_1}

,

\mathrm{B_2}

,

\mathrm{B_3}

....... ;

\mathrm{B_1}

has lowest energy among Balmer lines). The energy of

\mathrm{L_1}

is x times the energy of

\mathrm{B_1}

. The value of x is ______

\times 10^{-1}

(Nearest inteter)

Q21·ChemistrySingle correctJEE Main 2026

Which of the following statements regarding the energy of the stationary state is true in the following one-electron system ?

(A) $-1.09 \times 10^{-18}$ J for second orbit of H atom.
(B) $+2.18 \times 10^{-18}$ J for second orbit of He $^+$ ion
(C) $+8.72 \times 10^{-18}$ J for first orbit of He $^+$ ion
(D) $-2.18 \times 10^{-18}$ J for third orbit of Li $^{2+}$ ion

Q22·ChemistrySingle correctJEE Main 2026

Given, (A) n = 5, m

_l

=

-1

(B) n = 3, l = 2, m

_l

=

-1

, m

_s

=

+\frac{1}{2}

The maximum number of electron(s) in an atom that can have the quantum numbers as given in (A) and (B) respectively are :

(A)26 and 1
(B)4 and 1
(C)2 and 4
(D)8 and 1

Q23·ChemistrySingle correctJEE Main 2026

The work functions of two metals (M

_{A}

and M

_{B}

) are in the 1 : 2 ratio. When these metals are exposed to photons of energy 6 eV, the kinetic energy of liberated electrons of M

_{A}

: M

_{B}

is in the ratio of 2.642 : 1. The work functions (in eV) of M

_{A}

and M

_{B}

are respectively.

(A)3.1, 6.2
(B)2.3, 4.6
(C)1.4, 2.8
(D)1.5, 3.0

Q24·ChemistrySingle correctJEE Main 2026

Identify the INCORRECT statements from the following: A. Notation

_{12}^{24}

Mg represents 24 protons and 12 neutrons. B. Wavelength of a radiation of frequency 4.5 × 10

^{15}

s

^{-1}

is 6.7 × 10

^{-8}

m. C. One radiation has wavelength =

\lambda_{1}

(900 nm) and energy = E

_{1}

. Other radiation has wavelength =

\lambda_{2}

(300 nm) and energy = E

_{2}

.E

_{1}

: E

_{2}

= 3 : 1. D. Number of photons of light of wavelength 2000 pm that provides 1 J of energy is 1.006 × 10

^{16}

. Choose the correct answer from the options given below:

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

Q25·ChemistrySingle correctJEE Main 2026

The energy required by electrons, present in the first Bohr orbit of hydrogen atom to be excited to second Bohr orbit is ________ J mol

^{-1}

. Given : R

_H

= 2.18 × 10

^{-11}

ergs.

(A)1.635 × 10 $^{-18}$
(B)9.835 × 10 $^{5}$
(C)9.835 × 10 $^{12}$
(D)1.635 × 10 $^{-11}$

Q26·ChemistrySingle correctJEE Main 2026

The energy of first (lowest) Balmer line of H atom is x J. The energy (in J) of second Balmer line of H atom is :

(A) $x^{2}$
(B) $\frac{x}{1.35}$
(C)2x
(D)1.35 x

Q27·ChemistrySingle correctJEE Main 2026

Consider the following spectral lines for atomic hydrogen: A. First line of Paschen series B. Second line of Balmer series C. Third line of Paschen series D. Fourth line of Bracket sereis The correct arrangement of the above lines in ascending order of energy is:

(A) $\text{D} < \text{C} < \text{A} < \text{B}$
(B) $\text{A} < \text{B} < \text{C} < \text{D}$
(C) $\text{C} < \text{D} < \text{B} < \text{A}$
(D) $\text{D} < \text{A} < \text{C} < \text{B}$

Q28·ChemistrySingle correctJEE Main 2026

Given below are two statements: Statement I: When an electric discharge is passed through gaseous hydrogen, the hydrogen molecules dissociate and the energetically excited hydrogen atoms produce electromagnetic radiation of discrete frequencies. Statement II: The frequency of second line of Balmer series obtained from He

^+

is equal to that of first line of Lyman series obtained from hydrogen atom. 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 false but Statement II is true
(D)Statement I is true but Statement II is false

Q29·ChemistryIntegerJEE Main 2025

The energy of an electron in first Bohr orbit of H-atom is

-13.6

eV. The magnitude of energy value of electron in the first excited state of

Be^{3+}

is ___ eV. (nearest integer value)

Q30·ChemistrySingle correctJEE Main 2025

Correct statements for an element with atomic number 9 are: A. There can be 5 electrons for which

m_s=+\dfrac{1}{2}

and 4 electrons for which

m_s=-\dfrac{1}{2}

. B. There is only one electron in

p_x

orbital. C. The last electron goes to orbital with

n=2

and

l=1

. D. The sum of angular nodes of all the atomic orbitals is 1. Choose the correct answer from the options given below:

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

Q31·ChemistrySingle correctJEE Main 2025

For the visible spectrum (wavelength 400 nm to 750 nm), which of the following statements are correct, if the threshold frequency of caesium is

5.16\times10^{14}

Hz? A. When Cs is placed inside a vacuum chamber with an ammeter connected to it and yellow light is focused on Cs the ammeter shows the presence of current. B. When the brightness of the yellow light is dimmed, the value of the current in the ammeter is reduced. C. When a red light is used instead to the yellow light, the current produced is higher with respect to the yellow light. D. When a blue light is used, the ammeter shows the formation of current. E. When a white light is used, the ammeter shows formation of current. Choose the correct answer from the options given below:

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

Q32·ChemistrySingle correctJEE Main 2025

The extra stability of half-filled subshell is due to: (A) Symmetrical distribution of electrons (B) Smaller coulombic repulsion energy (C) The presence of electrons with the same spin in non-degenerate orbitals (D) Larger exchange energy (E) Relatively smaller shielding of electrons by one another Identify the correct statements:

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

Q33·ChemistrySingle correctJEE Main 2025

Consider the ground state of chromium atom

(Z = 24)

. How many electrons are with Azimuthal quantum number

l = 1

and

l = 2

respectively?

(A)12 and 4
(B)16 and 4
(C)12 and 5
(D)16 and 5

Q34·ChemistrySingle correctJEE Main 2025

Which one of the following about an electron occupying the 1s orbital in a hydrogen atom is incorrect? (Bohr's radius is represented by

a_0

)

(A)The probability density of finding the electron is maximum at the nucleus
(B)The electron can be found at a distance $2a_0$ from the nucleus
(C)The 1s orbital is spherically symmetrical
(D)The total energy of the electron is maximum when it is at a distance $a_0$ from the nucleus

Q35·ChemistrySingle correctJEE Main 2025

For electron in '2s' and '2p' orbitals, the orbital angular momentum values, respectively are:

(A) $\sqrt2\,\dfrac{h}{2\pi}$ and 0
(B) $\dfrac{h}{2\pi}$ and $\sqrt2\,\dfrac{h}{2\pi}$
(C) $0$ and $\sqrt6\,\dfrac{h}{2\pi}$
(D) $0$ and $\sqrt2\,\dfrac{h}{2\pi}$

Q36·ChemistrySingle correctJEE Main 2025

Which of the following postulate of Bohr's model of hydrogen atom is not in agreement with quantum mechanical model of an atom?

(A)An atom in a stationary state does not emit electromagnetic radiation as long as it stays in the same state.
(B)An atom can take only certain distinct energies $E_1, E_2, E_3$ , etc. These allowed states of constant energy are called the stationary states of atom.
(C)When an electron makes a transition from a higher energy stationary state to a lower energy stationary state, then it emits a photon of light.
(D)The electron in a H atom's stationary state moves in a circle around the nucleus.

Q37·ChemistrySingle correctJEE Main 2025

Which of the following statements are true? (A) The subsidiary quantum number

l

describes the shape of the orbital occupied by the electron. (B) The boundary surface shown in the figure is the boundary surface diagram of the

2p_x

orbital. (C) The

+

and

-

signs in the wave function of the

2p_x

orbital refer to charge. (D) The wave function of

2p_x

orbital is zero everywhere in the xy plane. Choose the correct answer from the options given below:

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

Q38·ChemistrySingle correctJEE Main 2025

According to Bohr’s model of hydrogen atom, which of the following statement is incorrect?

(A)Radius of 3rd orbit is nine times larger than that of 1st orbit.
(B)Radius of 8th orbit is four times larger than that of 4th orbit.
(C)Radius of 6th orbit is three times larger than that of 4th orbit.
(D)Radius of 4th orbit is four times larger than that of 2nd orbit.

Q39·ChemistrySingle correctJEE Main 2025

For hydrogen like species, which of the following graphs provides the most appropriate representation of E vs Z plot for a constant a? [E: Energy of the stationary state, Z: atomic number, n = principal quantum number] (graphs shown in the figure)

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

Q40·ChemistrySingle correctJEE Main 2025

Given below are two statements: Statement (I): It is impossible to specify simultaneously with arbitrary precision, both the linear momentum and the position of a particle. Statement (II): If the uncertainty in the measurement of position and uncertainty in measurement of momentum are equal for an electron, then the uncertainty in the measurement of velocity is

\ge\dfrac{1}{2m}\sqrt{\dfrac{h}{\pi}}

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

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

Q41·ChemistrySingle correctJEE Main 2025

If

a_0

is denoted as the Bohr radius of hydrogen atom, then what is the de-Broglie wavelength (

\lambda

) of the electron present in the second orbit of hydrogen atom? [n: any integer]

(A) $\dfrac{2a_0}{n\pi}$
(B) $\dfrac{8\pi a_0}{n}$
(C) $\dfrac{4\pi a_0}{n}$
(D) $\dfrac{4n}{\pi a_0}$

Q42·ChemistrySingle correctJEE Main 2025

Which of the following is/are not correct with respect to energy of atomic orbitals of hydrogen atom? (A)

1s<2p<3d<4s

(B)

1s<2s=2p<3p

(C)

1s<2s<2p<3p

(D)

1s<2s<4s<3d

. Choose the correct answer from the options given below:

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

Q43·ChemistrySingle correctJEE Main 2025

In a multielectron atom, which of the following orbitals described by three quantum numbers with have same energy in absence of electric and magnetic fields? A.

n=1, l=0, m_l=0

B.

n=2, l=0, m_l=0

C.

n=2, l=1, m_l=1

D.

n=3, l=2, m_l=1

E.

n=3, l=2, m_l=0

. 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)D and E only

Q44·ChemistrySingle correctJEE Main 2025

For hydrogen atom, the orbital/s with lowest energy is/are : (A)

4s

(B)

3p_x

(C)

3d_{x^2-y^2}

(D)

3d_{z^2}

(E)

4p_z

. Choose the correct answer from the options given below :

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

Q45·ChemistrySingle correctJEE Main 2025

Heat treatment of muscular pain involves radiation of wavelength of about 900 nm. Which spectral line of H atom is suitable for this ? (Given: Rydberg constant

R_H=10^5

cm

^{-1}

,

h=6.6\times10^{-34}

J s,

c=3\times10^8

m/s)

(A)Paschen series, ∞→3
(B)Lyman series, ∞→1
(C)Balmer series, ∞→2
(D)Paschen series, 5→3

Q46·ChemistrySingle correctJEE Main 2025

Given below are two statements: Statement (I): For a given shell, the total number of allowed orbitals is given by

n^2

. Statement (II): For any subshell, the spatial orientation of the orbitals is given by

-l

to

+l

values including zero. In the light of the above statements, choose the correct 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

Q47·ChemistrySingle correctJEE Main 2025

The radius of the first excited state of a helium ion (He⁺) is given as ______, where a₀ = radius of the first stationary state of the hydrogen atom.

(A)a₀/2
(B)a₀/4
(C)4a₀
(D)2a₀

Q48·ChemistrySingle correctJEE Main 2025

Given below are two statements: Statement (I): A spectral line will be observed for a

2p_x \to 2p_y

transition. Statement (II):

2p_x

and

2p_y

are degenerate orbitals. 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.

Q49·ChemistrySingle correctJEE Advanced 2024

According to Bohr's model, the highest kinetic energy is associated with the electron in the

(A)first orbit of H atom
(B)first orbit of He $^{+}$
(C)second orbit of He $^{+}$
(D)second orbit of Li $^{2+}$

Q50·ChemistryMultiple correctJEE Advanced 2024

Among the following, the correct statement(s) for electrons in an atom is(are)

(A)Uncertainty principle rules out the existence of definite paths for electrons.
(B)The energy of an electrons in 2s orbital of an atom is lower than the energy of an electron that is infinitely far away from the nucleus.
(C)According to Bohr's model, the most negative energy value for an electron is given by n = 1, which corresponds to the most stable orbit.
(D)According to Bohr's model, the magnitude of velocity of electrons increases with increase in values of n.

Q51·ChemistrySingle correctJEE Main 2024

Match List-I (Element) with List-II (Electronic Configuration). Choose the correct answer from the options given below:

List-I (Element)	List-II (Electronic Configuration)
A.N	I. $[Ar]3d^{10}4s^24p^5$
B.S	II. $[Ne]3s^23p^4$
C.Br	III. $[He]2s^22p^3$
D.Kr	IV. $[Ar]3d^{10}4s^24p^6$

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

Q52·ChemistryNumericalJEE Main 2024

Based on Heisenberg's uncertainty principle, the uncertainty in the velocity of the electron to be found within an atomic nucleus of diameter

10^{-15}

m is _______

\times10^{9}

m s

^{-1}

(nearest integer). [Given: mass of electron

=9.1\times10^{-31}

kg, Planck's constant (

h

)

=6.626\times10^{-34}

J s]

Q53·ChemistrySingle correctJEE Main 2024

Compare the energies of following sets of quantum numbers for multielectron system. (A)

n = 4, l = 1

; (B)

n = 4, l = 2

; (C)

n = 3, l = 1

; (D)

n = 3, l = 2

; (E)

n = 4, l = 0

. Choose the correct answer from the options given below :

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

Q54·ChemistryNumericalJEE Main 2024

Wavenumber for a radiation having 5800 Å wavelength is

x\times10

cm

^{-1}

. The value of x is _______ .

Q55·ChemistryNumericalJEE Main 2024

A hypothetical electromagnetic wave is shown in the figure (wavelength marked). The frequency of the wave is

x\times10^{19}

Hz.

x=

___ (nearest integer)

Q56·ChemistryNumericalJEE Main 2024

For hydrogen atom, energy of an electron in first excited state is

-3.4

eV, K.E. of the same electron of hydrogen atom is x eV. Value of x is _______

\times 10^{-1}

eV. (Nearest integer)

Q57·ChemistryNumericalJEE Main 2024

Frequency of the de-Broglie wave of an electron in Bohr's first orbit of hydrogen atom is _______

\times10^{13}

Hz (nearest integer). (Given:

R_H

(Rydberg constant)

=2.18\times10^{-18}

J;

h

(Planck's constant)

=6.6\times10^{-34}

J s)

Q58·ChemistryNumericalJEE Main 2024

In an atom, the total number of electrons having quantum numbers

n = 4

,

|m_l| = 1

and

m_s = -\tfrac{1}{2}

is __________.

Q59·ChemistryNumericalJEE Main 2024

The value of the Rydberg constant

R_H

is

2.18\times10^{-18}

J. The velocity of an electron of mass

9.1\times10^{-31}

kg in Bohr's first orbit of the hydrogen atom is ___

\times10^{6}\ \text{ms}^{-1}

(nearest integer).

Q60·ChemistryNumericalJEE Main 2024

The de-Broglie's wavelength of an electron in the

4^{th}

orbit is ___

\pi a_0

. (

a_0

= Bohr's radius)

Q61·ChemistryNumericalJEE Main 2024

The maximum number of orbitals which can be identified with

n=4

and

m_l=0

is ______.

Q62·ChemistrySingle correctJEE Main 2024

The number of radial node/s for 3p orbital is:

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

Q63·ChemistrySingle correctJEE Main 2024

According to the wave-particle duality of matter by de-Broglie, which of the following graph plot presents most appropriate relationship between wavelength of electron

(\lambda)

and momentum of electron

(p)

?

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

Q64·ChemistrySingle correctJEE Main 2024

The four quantum numbers for the electron in the outer most orbital of potassium (atomic no. 19) are

(A) $n=4,\ \ell=2,\ m=-1,\ s=+\dfrac{1}{2}$
(B) $n=4,\ \ell=0,\ m=0,\ s=+\dfrac{1}{2}$
(C) $n=3,\ \ell=0,\ m=0,\ s=+\dfrac{1}{2}$
(D) $n=2,\ \ell=0,\ m=0,\ s=+\dfrac{1}{2}$

Q65·ChemistryNumericalJEE Main 2024

The ionization energy of sodium in kJ mol

^{-1}

, if electromagnetic radiation of wavelength 242 nm is just sufficient to ionize sodium atom, is ______.

Q66·ChemistryNumericalJEE Main 2024

Number of spectral lines obtained in

He^+

spectra, when an electron makes transition from fifth excited state to first excited state will be ______.

Q67·ChemistrySingle correctJEE Main 2024

Given below are two statements: Statement-I: The orbitals having same energy are called as degenerate orbitals. Statement-II: In hydrogen atom, 3p and 3d are not degenerate orbitals. 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)Both Statement-I and Statement-II are true.
(C)Both Statement-I and Statement-II are false
(D)Statement-I is false but Statement-II is true

Q68·ChemistrySingle correctJEE Main 2024

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

List I (Spectral Series for Hydrogen)	List II (Spectral Region)
A.Lyman	I.Infrared region
B.Balmer	II.UV region
C.Paschen	III.Infrared region
D.Pfund	IV.Visible region

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

Q69·ChemistrySingle correctJEE Main 2024

The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is :

(A) $5,0,0,+\dfrac{1}{2}$
(B) $5,0,1,+\dfrac{1}{2}$
(C) $5,1,0,+\dfrac{1}{2}$
(D) $5,1,1,+\dfrac{1}{2}$

Q70·ChemistryNumericalJEE Main 2024

Total number of ions from the following that have noble gas electronic configuration is __________.

Sr^{2+}

(Z=38),

Cs^+

(Z=55),

La^{3+}

(Z=57),

Pb^{2+}

(Z=82),

Yb^{2+}

(Z=70),

Fe^{2+}

(Z=26).

Q71·ChemistrySingle correctJEE Main 2024

The electronic configuration for Neodymium is: [Atomic Number for Neodymium 60]

(A) $[\text{Xe}]\,4f^4\,6s^2$
(B) $[\text{Xe}]\,5f^4\,7s^2$
(C) $[\text{Xe}]\,6f^4\,6s^2$
(D) $[\text{Xe}]\,4f^5\,5d^1\,6s^2$

Q72·ChemistryNumericalJEE Main 2024

The number of electrons present in all the completely filled subshells having

n=4

and

s=+\dfrac{1}{2}

is __________. (Where

n=

principal quantum number and

s=

spin quantum number)

Q73·ChemistryIntegerJEE Advanced 2023

For

\mathrm{He^{+}}

, a transition takes place from the orbit of radius 105.8 pm to the orbit of radius 26.45 pm. The wavelength (in nm) of the emitted photon during the transition is ___. [Use: Bohr radius, a = 52.9 pm Rydberg constant,

R_H = 2.2 \times 10^{-18}

J Planck's constant, h =

6.6 \times 10^{-34}

J s Speed of light, c =

3 \times 10^{8}

m s

^{-1}

]

Q74·ChemistryNumericalJEE Main 2023

The total number of isoelectronic species from the given set is _______

O^{2-}, F^-, Al, Mg^{2+}, Na^+, O^+, Mg, Al^{3+}, F

Q75·ChemistrySingle correctJEE Main 2023

Given below are two statements: Statement I: According to Bohr's model of hydrogen atom, the angular momentum of an electron in a given stationary state is quantised. Statement II: The concept of electron in Bohr's orbit, violates the Heisenberg uncertainty principle. 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.

Q76·ChemistrySingle correctJEE Main 2023

The energy of an electron in the first Bohr orbit of hydrogen atom is

-2.18\times10^{-18}\,J

. Its energy in the third Bohr orbit is:

(A) $\dfrac{1}{27}$ of this value
(B)One third of this value
(C)Three times of this value
(D) $\dfrac{1}{9}$ th of this value

Q77·ChemistryNumericalJEE Main 2023

The orbital angular momentum of an electron in 3s orbital is

\dfrac{xh}{2\pi}

. The value of x is

Q78·ChemistryNumericalJEE Main 2023

Values of work function (

W_0

) for a few metals are given below — Metal: Li, Na, K, Mg, Cu, Ag;

W_0

/eV: 2.42, 2.3, 2.25, 3.7, 4.8, 4.3. The number of metals which will show photoelectric effect when light of wavelength 400nm falls on it is _________. Given: h = 6.6 × 10

^{-34}

J s; c = 3 × 10

^8

m s

^{-1}

; e = 1.6 × 10

^{-19}

C.

Q79·ChemistryNumericalJEE Main 2023

The number of correct statements from the following is ____. A. For 1s orbital, the probability density is maximum at the nucleus. B. For 2s orbital, the probability density first increases to a maximum and then decreases sharply to zero. C. Boundary surface diagrams of the orbitals enclose a region of 100% probability of finding the electron. D. p and d-orbitals have 1 and 2 angular nodes respectively. E. Probability density of a p-orbital is zero at the nucleus.

Q80·ChemistrySingle correctJEE Main 2023

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R: Assertion A: In the photoelectric effect, the electrons are ejected from the metal surface as soon as the beam of light of frequency greater than threshold frequency strikes the surface. Reason R: When the photon of any energy strikes an electron in the atom, transfer of energy from the photon to the electron takes place. In the light of the above statements, choose the most appropriate answer from the options given below:

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

Q81·ChemistryNumericalJEE Main 2023

The electron in the

n^{\text{th}}

orbit of

\text{Li}^{2+}

is excited to the

(n+1)

orbit using radiation of energy

1.47\times10^{-17}

J. The value of n is _______ . (Given

R_H=2.18\times10^{-18}

J).

Q82·ChemistryNumericalJEE Main 2023

The number of incorrect statement/s about the black body from the following is _________. (A) Emit or absorb energy in the form of electromagnetic radiation. (B) Frequency distribution of the emitted radiation depends on temperature. (C) At a given temperature, intensity vs frequency curve passes through a maximum value. (D) The maximum of the intensity vs frequency curve is at a higher frequency at higher temperature compared to that at lower temperature.

Q83·ChemistryNumericalJEE Main 2023

The number of atomic orbitals from the following having 5 radial nodes is ____. 7s, 7p, 6s, 8p, 8d

Q84·ChemistryNumericalJEE Main 2023

The number of following statement/s which is/are incorrect is ____ (A) Line emission spectra are used to study the electronic structure (B) The emission spectra of atoms in the gas phase show a continuous spread of wavelength from red to violet (C) An absorption spectrum is like the photographic negative of an emission spectrum (D) The element helium was discovered in the sun by spectroscopic method

Q85·ChemistrySingle correctJEE Main 2023

Henry Moseley studied the characteristic X-ray spectra of elements. The graph which represents his observation correctly is: (Given

v=

frequency of X-ray emitted;

Z=

atomic number)

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

Q86·ChemistrySingle correctJEE Main 2023

If the radius of the first orbit of hydrogen atom is

a_0

, then de Broglie's wavelength of electron in

3^{rd}

orbit is

(A) $\frac{\pi a_0}{2}$
(B) $\frac{\pi a_0}{3}$
(C) $6\pi a_0$
(D) $3\pi a_0$

Q87·ChemistryNumericalJEE Main 2023

The wavelength of an electron of kinetic energy

4.50\times10^{-29}\,J

is _____

\times 10^{-5}\,m

. (Nearest integer) Given: mass of electron is

9\times10^{-31}\,kg,\,h=6.6\times10^{-34}\,J\,s

.

Q88·ChemistryNumericalJEE Main 2023

Electrons in a cathode ray tube have been emitted with a velocity of

1000

m s

^{-1}

. The number of following statements which is/are true about the emitted radiation is _______ . (Given:

h=6\times10^{-34}

Js,

m_e=9\times10^{-31}

kg) (A) The deBroglie wavelength of the electron is

666.67

nm. (B) The characteristic of electrons emitted depend upon the material of the electrodes of the cathode ray tube. (C) The cathode rays start from cathode and move towards anode. (D) The nature of the emitted electrons depends on the nature of the gas present in cathode ray tube.

Q89·ChemistrySingle correctJEE Main 2023

Which one of the following sets of ions represents a collection of isoelectronic species? (Given Atomic Number: F:9, Cl:17, Na=11, Mg=12, Al=13, K=19, Ca=20, Sc=21)

(A) $Ba^{2+},Sr^{2+},K^+,Ca^{2+}$
(B) $Li^+,Na^+,Mg^{2+},Ca^{2+}$
(C) $N^{3-},O^{2-},F^-,S^{2-}$
(D) $K^+,Cl^-,Ca^{2+},Sc^{3+}$

Q90·ChemistrySingle correctJEE Main 2023

Arrange the following orbitals in decreasing order of energy. A. n=3, l=0, m=0 B. n=4, l=0, m=0 C. n=3, l=1, m=0 D. n=3, l=2, m=1. The correct option for the order is:

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

Q91·ChemistrySingle correctJEE Main 2023

Which transition in the hydrogen spectrum would have the same wavelength as the Balmer type transition from

n = 4

to

n = 2

of

He^+

spectrum

(A) $n = 2$ to $n = 1$
(B) $n = 1$ to $n = 2$
(C) $n = 3$ to $n = 4$
(D) $n = 1$ to $n = 3$

Q92·ChemistrySingle correctJEE Main 2023

The wave function (

\Psi

) of 2s is given by

\Psi_{2s}=\dfrac{1}{2\sqrt{2\pi}}\left(\dfrac{1}{a_0}\right)^{1/2}\left(2-\dfrac{r}{a_0}\right)e^{-r/2a_0}

. At

r=r_0

, a radial node is formed. Thus

r_0

in terms of

a_0

is:

(A) $r_0=4a_0$
(B) $r_0=\dfrac{a_0}{2}$
(C) $r_0=a_0$
(D) $r_0=2a_0$

Q93·ChemistryNumericalJEE Main 2023

The energy of one mole of photons of radiation of frequency

2\times10^{12}

Hz in J mol

^{-1}

is _________. (Nearest integer) [Given: h =

6.626\times10^{-34}

Js, N

_A

=

6.022\times10^{23}

mol

^{-1}

]

Q94·ChemistrySingle correctJEE Main 2023

The maximum number of electrons that can be accommodated in the shell with

n=4

is:

(A)16
(B)32
(C)72
(D)50

Q95·ChemistryNumericalJEE Main 2023

The radius of the first Bohr orbit of hydrogen atom is

0.6\,\mathring{A}

. The radius of the third Bohr orbit of

He^+

is _____ picometer. (Nearest Integer)

Q96·ChemistrySingle correctJEE Main 2023

The shortest wavelength of hydrogen atom in Lyman series is

\lambda

. The longest wavelength in Balmer series of He

^+

is:

(A) $\dfrac{36\lambda}{5}$
(B) $\dfrac{9\lambda}{5}$
(C) $\dfrac{5}{9\lambda}$
(D) $\dfrac{5\lambda}{9}$

Q97·ChemistrySingle correctJEE Main 2023

The radius of the

2^{nd}

orbit of

Li^{2+}

is

x

. The expected radius of the

3^{rd}

orbit of

Be^{3+}

is:

(A) $\dfrac{27}{16}x$
(B) $\dfrac{4}{9}x$
(C) $\dfrac{9}{4}x$
(D) $\dfrac{16}{27}x$

Q98·ChemistryNumericalJEE Main 2023

The number of given orbitals which have electron density along the axis is

P_x, P_y, P_z, d_{xy}, d_{yz}, d_{xz}, d_{z^2}, d_{x^2-y^2}

Q99·ChemistrySingle correctJEE Main 2023

It is observed that characteristic X-ray spectra of elements show regularity. When frequency to the power 'n' i.e.

v^n

of X-rays emitted is plotted against atomic number 'Z', the following graph is obtained. The value of 'n' is:

(A)3
(B)2
(C)1
(D) $\tfrac{1}{2}$

Q100·ChemistrySingle correctJEE Main 2023

The number of s-electrons present in an ion with

55

protons in its unipositive state is

(A) $8$
(B) $10$
(C) $9$
(D) $12$

Q101·ChemistryNumericalJEE Main 2023

Following figure shows spectrum of an ideal black body at four different temperatures. The number of correct statement/s from the following is _________. A.

T_4>T_3>T_2>T_1

. B. The black body consists of particles performing simple harmonic motion. C. The peak of the spectrum shifts to shorter wavelength as temperature increases. D.

\dfrac{T_1}{\nu_1}=\dfrac{T_2}{\nu_2}=\dfrac{T_3}{\nu_3}\neq

constant. E. The spectrum could be explained using quantisation of energy.

Q102·ChemistryNumericalJEE Main 2023

If wavelength of the first line of the Paschen series of hydrogen atom is 720 nm, then the wavelength of the second line of this series is _______ nm. (Nearest integer)

Q103·ChemistrySingle correctJEE Main 2022

Given below are the quantum numbers for 4 electrons. A. n = 3,

l

= 2, m

_{l}

= 1, m

_{s}

= +1/2 B. n = 4,

l

= 1, m

_{l}

= 0, m

_{s}

= +1/2 C. n = 4,

l

= 2, m

_{l}

= −2, m

_{s}

= −1/2 D. n = 3,

l

= 1, m

_{l}

= −1, m

_{s}

= +1/2 The correct order of increasing energy is :

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

Q104·ChemistryNumericalJEE Main 2022

The minimum uncertainty in the speed of an electron in an one dimensional region of length

2a_{0}

(Where

a_{0}

= Bohr radius 52.9 pm) is ______ km

s^{-1}

. (Given : Mass of electron = 9.1 ×

10^{-31}

kg, Planck's constant h = 6.63 ×

10^{-34}

Js)

Q105·ChemistrySingle correctJEE Main 2022

Identify the incorrect statement from the following.

(A)A circular path around the nucleus in which an electron moves is proposed as Bohr's orbit.
(B)An orbital is the one electron wave function (Ψ) in an atom.
(C)The existence of Bohr's orbits is supported by hydrogen spectrum.
(D)Atomic orbital is characterised by the quantum numbers n and $l$ only

Q106·ChemistryNumericalJEE Main 2022

If the wavelength for an electron emitted from H-atom is

3.3\times10^{-10}

m, then energy absorbed by the electron in its ground state compared to minimum energy required for its escape from the atom, is _____ times. (Nearest integer). [Given : h =

6.626\times10^{-34}

Js, Mass of electron =

9.1\times10^{-31}

]

Q107·ChemistrySingle correctJEE Main 2022

The correct decreasing order of energy, for the orbitals having, following set of quantum numbers: (A) n = 3, l = 0, m = 0 (B) n = 4, l = 0, m = 0 (C) n = 3, l = 1, m = 0 (D) n = 3, l = 2, m = 1

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

Q108·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 : Energy of 2s orbital of hydrogen atom is greater than that of 2s orbital of lithium. Reason R : Energies of the orbitals in the same subshell decrease with increase in the atomic number. 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.

Q109·ChemistryNumericalJEE Main 2022

The wavelength of an electron and a neutron will become equal when the velocity of the electron is x times the velocity of neutron. The value of x is__________. (Nearest Integer) (Mass of electron is 9.1 × 10

^{-31}

kg and mass of neutron is 1.6 × 10

^{-27}

kg)

Q110·ChemistryNumericalJEE Main 2022

Consider an imaginary ion

^{48}_{22}X^{3-}

. The nucleus contains 'a'% more neutrons than the number of electrons in the ion. The value of 'a' is ____. [nearest integer]

Q111·ChemistrySingle correctJEE Main 2022

Which of the following sets of quantum numbers is not allowed ?

(A) $n = 3, l = 2, m_{l} = 0, s = +\frac{1}{2}$
(B) $n = 3, l = 2, m_{l} = -2, s = +\frac{1}{2}$
(C) $n = 3, l = 3, m_{l} = -3, s = -\frac{1}{2}$
(D) $n = 3, l = 0, m_{l} = 0, s = -\frac{1}{2}$

Q112·ChemistrySingle correctJEE Main 2022

Which of the following statements are correct ? (A) The electronic configuration of Cr is [Ar]

3d^5 4s^1

. (B) The magnetic quantum number may have a negative value. (C) In the ground state of an atom, the orbitals are filled in order of their increasing energies. (D) The total number of nodes are given by n – 2 . Choose the most appropriate answer from the options given below :

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

Q113·ChemistrySingle correctJEE Main 2022

Which of the following is the correct plot for the probability density

\psi^2

(r) as a function of distance 'r' of the electron form the nucleus for 2s orbital?

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

Q114·ChemistrySingle correctJEE Main 2022

Consider the following statements : (A) The principal quantum number ‘n’ is a positive integer with values of ‘n’ = 1, 2, 3, …. (B) The azimuthal quantum number ‘

l

’ for a given ‘n’ (principal quantum number) can have values as ‘

l

’ = 0, 1, 2, …. n (C) Magnetic orbital quantum number ‘m

_l

’ for a particular ‘

l

’ (azimuthal quantum number) has (2

l

+ 1) values. (D) ±1/2 are the two possible orientations of electron spin. (E) For

l

= 5, there will be a total of 9 orbital. Which of the above statements are correct?

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

Q115·ChemistryNumericalJEE Main 2022

If the work function of a metal is

6.63 \times 10^{-19}

J, the maximum wavelength of the photon required to remove a photoelectron from the metal is _______ nm. (Nearest integer) [Given : h =

6.63 \times 10^{-34}

J s, and c =

3 \times 10^{8}

m

s^{-1}

]

Q116·ChemistryNumericalJEE Main 2022

Consider the following set of quantum numbers n l m

_l

A. 3 3 -3 B. 3 2 -2 C. 2 1 +1 D. 2 2 +2 The number of correct sets of quantum numbers is ________

Q117·ChemistryNumericalJEE Main 2022

If the uncertainty in velocity and position of a minute particle in space are, 2.4 ×

10^{-26}

(ms

^{-1}

) and

10^{-7}

(m) respectively. The mass of the particle in g is __________ (Nearest integer) (Given : h = 6.626 ×

10^{-34}

Js)

Q118·ChemistrySingle correctJEE Main 2022

If the radius of the

3^{rd}

Bohr's orbit of hydrogen atom is

r_{3}

and the radius of

4^{th}

Bohr's orbit is

r_{4}

. Then :

(A) $r_{4} = \frac{9}{16} r_{3}$
(B) $r_{4} = \frac{16}{9} r_{3}$
(C) $r_{4} = \frac{3}{4} r_{3}$
(D) $r_{4} = \frac{4}{3} r_{3}$

Q119·ChemistrySingle correctJEE Main 2022

The number of radial and angular nodes in 4d orbital are, respectively

(A)1 and 2
(B)3 and 2
(C)1 and 0
(D)2 and 1

Q120·ChemistrySingle correctJEE Main 2022

The minimum energy that must be possessed by photons in order to produce the photoelectric effect with platinum metal is: [Given: The threshold frequency of platinum is 1.3

\times

10

^{15}

s

^{-1}

and h = 6.6

\times

10

^{-34}

J s.]

(A)3.21 $\times$ 10 $^{-14}$ J
(B)6.24 $\times$ 10 $^{-16}$ J
(C)8.58 $\times$ 10 $^{-19}$ J
(D)9.76 $\times$ 10 $^{-20}$ J

Q121·ChemistryNumericalJEE Main 2022

The longest wavelength of light that can be used for the ionisation of lithium atom (Li) in its ground state is x ×

10^{-8}

m. The value of x is ____________. (Nearest Integer) (Given : Energy of the electron in the first shell of the hydrogen atom is −2.2 ×

10^{-18}

J; h = 6.63 ×

10^{-34}

Js and c = 3 ×

10^{8}

ms^{-1}

)

Q122·ChemistrySingle correctJEE Main 2022

Consider the following pairs of electrons (A) (a)

n = 3

,

\ell = 1

,

m_\ell = 1

,

m_s = +\dfrac{1}{2}

(b)

n = 3

,

\ell = 2

,

m_\ell = 1

,

m_s = +\dfrac{1}{2}

(B) (a)

n = 3

,

\ell = 2

,

m_\ell = -2

,

m_s = -\dfrac{1}{2}

(b)

n = 3

,

\ell = 2

,

m_\ell = -1

,

m_s = -\dfrac{1}{2}

(C) (a)

n = 4

,

\ell = 2

,

m_\ell = 2

,

m_s = +\dfrac{1}{2}

(b)

n = 3

,

\ell = 2

,

m_\ell = 2

,

m_s = +\dfrac{1}{2}

The pairs of electron present in degenerate orbitals is/are:

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

Q123·ChemistrySingle correctJEE Main 2022

The energy of one mole of photons of radiation of wavelength 300 nm is (Given : h =

6.63 \times 10^{-34}

Js, N

_A

=

6.02 \times 10^{23}

mol

^{-1}

, c =

3 \times 10^{8}

ms

^{-1}

)

(A)235 kJ mol $^{-1}$
(B)325 kJ mol $^{-1}$
(C)399 kJ mol $^{-1}$
(D)435 kJ mol $^{-1}$

Q124·ChemistryIntegerJEE Advanced 2021

Consider a helium (He) atom that absorbs a photon of wavelength 330 nm. The change in the velocity (in cm s

^{-1}

) of He atom after the photon absorption is ___. (Assume: Momentum is conserved when photon is absorbed. Use: Planck constant =

6.6 \times 10^{-34}

J s, Avogadro number =

6 \times 10^{23}

mol

^{-1}

, Molar mass of He = 4 g mol

^{-1}

)

Q125·ChemistryNumericalJEE Main 2021

A 50 watt bulb emits monochromatic red light of wavelength of 795 nm. The number of photons emitted per second by the bulb is x × 10

^{20}

. The value of x is ______ . [Given : h = 6.63 × 10

^{-34}

Js and c = 3.0 × 10

^{8}

ms

^{-1}

]

Q126·ChemistryNumericalJEE Main 2021

Ge(Z = 32) in its ground state electronic configuration has x completely filled orbitals with

\mathrm{m_{l}}

= 0. The value of x is ___.

Q127·ChemistryNumericalJEE Main 2021

The value of magnetic quantum number of the outermost electron of

\mathrm{Zn^+}

ion is __________.

Q128·ChemistryNumericalJEE Main 2021

The number of photons emitted by a monochromatic (single frequency) infrared range finder of power 1 mW and wavelength of 1000 nm, in 0.1 second is x × 10

^{13}

. The value of x is _____ . (Nearest integer) (h = 6.63 × 10

^{-34}

Js, c = 3.00 × 10

^{8}

ms

^{-1}

)

Q129·ChemistryNumericalJEE Main 2021

The kinetic energy of an electron in the second Bohr orbit of a hydrogen atom is equal to

\dfrac{h^2}{xma_0^2}

. The value of 10x is ________ . (

a_0

is radius of Bohr's orbit) (Nearest integer) [Given :

\pi = 3.14

]

Q130·ChemistryNumericalJEE Main 2021

A metal surface is exposed to 500 nm radiation. The threshold frequency of the metal for photoelectric current is

4.3 \times 10^{14}

Hz. The velocity of ejected electron is ______

\times 10^{5}

ms

^{-1}

(Nearest integer) [Use : h

= 6.63 \times 10^{-34}

Js,

m_e = 9.0 \times 10^{-31}

kg]

Q131·ChemistrySingle correctJEE Main 2021

Given below are two statements. Statement I: According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in positive charges on the nucleus as there is no strong hold on the electron by the nucleus. Statement II: According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in principal quantum number. 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 false
(B)Both Statement I and Statement II are true
(C)Statement I is false but Statement II is true
(D)Statement I is true but Statement II is false

Q132·ChemistrySingle correctJEE Main 2021

If the Thompson model of the atom was correct, then the result of Rutherford's gold foil experiment would have been:

(A)All α − particles get bounced back by 180°.
(B)α − particles are deflected over a wide range of angles.
(C)All of α − particles pass through the gold foil without decrease in speed.
(D)α − particles pass through the gold foil deflected by small angles and with reduced speed.

Q133·ChemistrySingle correctJEE Main 2021

Given below are two statements: Statement I: Rutherford's gold foil experiment cannot explain the line spectrum of hydrogen atom. Statement II: Bohr's model of hydrogen atom contradicts Heisenberg's uncertainty principle. 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)Both Statement I and Statement II are false.
(C)Both Statement I and Statement II are true.
(D)Statement I is false but Statement II is true.

Q134·ChemistryNumericalJEE Main 2021

An accelerated electron has speed of

5\times10^{6}

ms

^{-1}

with an uncertainty of 0.02%. The uncertainty in finding its location while in motion is x

\times

10^{-9}

m . The value of x is________. (Nearest integer) [Use mass of electron =

9.1\times10^{-31}

kg, h =

6.63\times10^{-34}

Js,

\pi

=3.14]

Q135·ChemistryNumericalJEE Main 2021

A source of monochromatic radiation of wavelength 400 nm provides 1000 J of energy in 10 seconds. When this radiation falls on the surface of sodium, x

\times 10^{20}

electrons are ejected per second. Assume that wavelength 400 nm is sufficient for ejection of electron from the surface of sodium metal. The value of x is________(Nearest integer) ( h = 6.626

\times 10^{-34}

Js)

Q136·ChemistryNumericalJEE Main 2021

The wavelength of electrons accelerated from rest through a potential difference of 40 kV is

x \times 10^{-12}

m. The value of

x

is ________. (Nearest Integer) Given : Mass of electron

= 9.1 \times 10^{-31}\ \mathrm{kg}

Charge on an electron

= 1.6 \times 10^{-19}\ \mathrm{C}

Planck's constant

= 6.63 \times 10^{-34}\ \mathrm{Js}

Q137·ChemistryNumericalJEE Main 2021

The Azimuthal quantum number for the valence electrons of Ga

^+

ion is______________. (Atomic number of Ga= 31)

Q138·ChemistrySingle correctJEE Main 2021

A certain orbital has no angular nodes and two radial nodes. The orbital is :

(A)2s
(B)3s
(C)3p
(D)2p

Q139·ChemistrySingle correctJEE Main 2021

Given below are two statements : Statement I : Bohr's theory accounts for the stability and line spectrum of Li

^{+}

ion. Statement II : Bohr's theory was unable to explain the splitting of spectral lines in the presence of a magnetic field. 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 true.
(B)Statement I is false but statement II is true.
(C)Both statement I and statement II are false.
(D)Statement I is true but statement II is false.

Q140·ChemistryNumericalJEE Main 2021

A certain orbital has n = 4 and

\mathrm{m_L} = -3

. The number of radial nodes in this orbital is ________. (Round off to the Nearest Integer).

Q141·ChemistryNumericalJEE Main 2021

When light of wavelength 248 nm falls on a metal of threshold energy 3.0 eV, the de-Broglie wavelength of emitted electrons is _______ Å. (Round off to the Nearest Integer). [Use :

\sqrt{3}

= 1.73, h = 6.63 × 10

^{-34}

Js m

_{e}

= 9.1 × 10

^{-31}

kg ; c = 3.0 × 10

^{8}

ms

^{-1}

; 1eV = 1.6 × 10

^{-19}

J]

Q142·ChemistryNumericalJEE Main 2021

The number of orbitals with n = 5, m

_{1}

= + 2 is ______. (Round off to the Nearest Integer).

Q143·ChemistrySingle correctJEE Main 2021

The orbital having two radial as well as two angular nodes is

(A)5d
(B)4f
(C)3p
(D)4d

Q144·ChemistryNumericalJEE Main 2021

A ball weighing 10g is moving with a velocity of 90ms

^{-1}

. If the uncertainty in its velocity is 5%, then the uncertainty in its position is _________

\times10^{-33}

m. (Rounded off to the nearest integer) [Given : h =

6.63\times10^{-34}

Js]

Q145·ChemistryNumericalJEE Main 2021

Electromagnetic radiation of wavelength 663 nm is just sufficient to ionize the atom of metal A. The ionization energy of metal A in kJ mol

^{—1}

is____. (Rounded off to the nearest integer) [h=6.63×10

^{-34}

Js, c = 3.00×10

^{8}

ms

^{-1}

, NA=6.02×10

^{23}

mol

^{-1}

]

Q146·ChemistrySingle correctJEE Main 2021

The plots of radial distribution functions for various orbitals of hydrogen atom against 'r' are given below: The correct plot for 3s orbital is:

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

Q147·ChemistryNumericalJEE Main 2021

A proton and a

\mathrm{Li^{3+}}

nucleus are accelerated by the same potential. If

\lambda_{\mathrm{Li}}

and

\lambda_{\mathrm{p}}

denote the de Broglie wavelengths of

\mathrm{Li^{3+}}

and proton respectively, then the value of

\dfrac{\lambda_{\mathrm{Li}}}{\lambda_{\mathrm{p}}}

is

x \times 10^{-1}

. The value of x is _________. [Rounded off to the nearest integer] [Mass of

\mathrm{Li^{3+}}

= 8.3 mass of proton]

Q148·ChemistrySingle correctJEE Main 2021

According to Bohr's atomic theory : (A) Kinetic energy of electron is

\propto \frac{Z^{2}}{n^{2}}

(B) The product of velocity (v) of electron and principal quantum number (n). 'vn'

\propto Z^{2}

. (C) Frequency of revolution of electron in an orbit is

\propto \frac{Z^{3}}{n^{3}}

. (D) Coulombic force of attraction on the electron is

\propto \frac{Z^{3}}{n^{4}}

. Choose the most appropriate answer from the options given below:

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

Q149·ChemistryNumericalJEE Advanced 2020

The figure below is the plot of potential energy versus internuclear distance (

d

) of

H_{2}

molecule in the electronic ground state. What is the value of the net potential energy

E_{0}

(as indicated in the figure) in kJ

mol^{-1}

, for

d = d_{0}

at which the electron-electron repulsion and the nucleus-nucleus repulsion energies are absent? As reference, the potential energy of H atom is taken as zero when its electron and the nucleus are infinitely far apart. Use Avogadro constant as

6.023 \times 10^{23}

mol^{-1}

.

Q150·ChemistrySingle correctJEE Main 2020

The difference between the radii of 3rd and 4th orbits of

Li^{2+}

in

\Delta R_1

.. The difference between the radii of 3rd and 4th orbits of

He^+

is

\Delta R_2

. Ratio

\Delta R_1 : \Delta R_2

is:

(A)8:3
(B)2:3
(C)3:8
(D)3:2

Q151·ChemistrySingle correctJEE Main 2020

The region in the electromagnetic spectrum where the Balmer series lines appear is:

(A)Ultraviolet
(B)Visible
(C)Infrared
(D)Microwave

Q152·ChemistrySingle correctJEE Main 2020

Consider the hypothetical situation where the azimuthal quantum number, l, takes values 0, 1, 2,…….n + 1, where n is the principal quantum number. Then, the element with atomic number:

(A)9 is the first alkali metal
(B)8 is the first noble gas
(C)13 has a half – filled valence subshell
(D)6 has a 2p – valence subshell

Q153·ChemistrySingle correctJEE Main 2020

The de Broglie wavelength of an electron in the 4

^{th}

Bohr orbit is:

(A) $6\pi a_0$
(B) $4\pi a_0$
(C) $2\pi a_0$
(D) $8\pi a_0$

Q154·ChemistrySingle correctJEE Main 2020

For the Balmer series in the spectrum of H atom,

\bar{\nu} = R_H \left\{\dfrac{1}{n_1^{2}} - \dfrac{1}{n_2^{2}}\right\}

the correct statements among (I) to (IV) are : (I) As wavelength decreases, the lines in the series converge (II) The integer n1 is equal to 2 (III) The lines of longest wavelength corresponds to n

_2

= 3 (IV) The ionization energy of hydrogen can be calculated from wave number of these lines

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

Q155·ChemistrySingle correctJEE Main 2020

The radius of the second Bohr orbit, in terms of the Bohr radius,

a_0

, in

Li^{2+}

is

(A) $\dfrac{4a_0}{3}$
(B) $\dfrac{2a_0}{9}$
(C) $\dfrac{2a_0}{3}$
(D) $\dfrac{4a_0}{9}$

Q156·ChemistrySingle correctJEE Main 2020

The number of orbitals associated with quantum number n = 5, m

_s

= +

\frac{1}{2}

is

(A)15
(B)11
(C)50
(D)25

Q157·ChemistrySingle correctJEE Advanced 2019

Consider the Bohr's model of a one-electron atom where the electron moves around the nucleus. In the following, List-I contains some quantities for the n

^{th}

orbit of the atom and List-II contains options showing how they depend on n. Which of the following options has the correct combination considering List-I and List-II?

LIST-I	LIST-II
I.Radius of the n $^{th}$ orbit	P. $\propto n^{-2}$
II.Angular momentum of the electron in the n $^{th}$ orbit	Q. $\propto n^{-1}$
III.Kinetic energy of the electron in the n $^{th}$ orbit	R. $\propto n^{0}$
IV.Potential energy of the electron in the n $^{th}$ orbit	S. $\propto n^{1}$
	T. $\propto n^{2}$
	U. $\propto n^{1/2}$

(A)(I), (T)
(B)(II), (R)
(C)(I), (P)
(D)(II), (Q)

Q158·ChemistryMultiple correctJEE Advanced 2019

In the decay sequence,

^{238}_{92}

U

\xrightarrow{-x_{1}}

^{234}_{90}

Th

\xrightarrow{-x_{2}}

^{234}_{91}

Pa

\xrightarrow{-x_{3}}

^{234}

Z

\xrightarrow{-x_{4}}

^{230}_{90}

Th x

_{1}

, x

_{2}

, x

_{3}

and x

_{4}

are particles /radiation emitted by the respective isotopes. The correct option(s) is(are)

(A)x $_{3}$ is $\gamma$ -ray
(B)Z is an isotope of uranium
(C)x $_{2}$ is $\beta^{-}$
(D)x $_{1}$ will deflect towards negatively charged plate

Q159·ChemistrySingle correctJEE Advanced 2019

Consider the Bohr's model of a one-electron atom where the electron moves around the nucleus. In the following, List-I contains some quantities for the n

^{th}

orbit of the atom and List-II contains options showing how they depend on n. Which of the following options has the correct combination considering List-I and List-II?

LIST-I	LIST-II
I.Radius of the n $^{th}$ orbit	P. $\propto n^{-2}$
II.Angular momentum of the electron in the n $^{th}$ orbit	Q. $\propto n^{-1}$
III.Kinetic energy of the electron in the n $^{th}$ orbit	R. $\propto n^{0}$
IV.Potential energy of the electron in the n $^{th}$ orbit	S. $\propto n^{1}$
	T. $\propto n^{2}$
	U. $\propto n^{1/2}$

(A)(III), (P)
(B)(IV), (U)
(C)(III), (S)
(D)(IV), (Q)

Q160·ChemistryMultiple correctJEE Advanced 2019

The ground state energy of hydrogen atom is

-

13.6 eV. Consider an electronic state

\psi

of He

^{+}

whose energy, azumuthal quantum number and magnetic quantum number are -3.4 eV, 2 and 0, respectively. Which of the following statement(s) is(are) true for the state

\psi

?

(A)It is a 4d state
(B)It has 2 angular nodes
(C)It has 3 radial nodes
(D)The nuclear charge experienced by the electron in this state is less than 2e, where e is the magnitude of the electronic charge

Q161·ChemistrySingle correctJEE Main 2019

The electrons are more likely to be found:

(A)in the region a and b
(B)in the region a and c
(C)only in the region a
(D)only in the region c

Q162·ChemistrySingle correctJEE Main 2019

Among the following, the energy of 2s orbital is lowest in:

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

Q163·ChemistrySingle correctJEE Main 2019

The ratio of the shortest wavelength of two spectral series of hydrogen spectrum is found to be about 9. The spectral series are:

(A)Lyman and Paschen
(B)Brackett and Pfund
(C)Paschen and Pfund
(D)Balmer and Brackett

Q164·ChemistrySingle correctJEE Main 2019

The graph between

|\psi|^{2}

and r(radial distance) is shown below. This represents:

(A)1s orbital
(B)3s orbital
(C)2s orbital
(D)2p orbital

Q165·ChemistrySingle correctJEE Main 2019

Which one of the following about an electron occupying the 1s orbital in a hydrogen atom is incorrect? (The Bohr radius is represented by a

_0

)

(A)The electron can be found at a distance 2a $_0$ from the nucleus
(B)The probability density of finding the electron is maximum at the nucleus
(C)The magnitude of potential energy is double that of its kinetic energy on an average
(D)The total energy of the electron is maximum when it is at a distance a $_0$ from the nucleus

Q166·ChemistrySingle correctJEE Main 2019

The quantum number of four electrons are given below: I.

n=4, l=2, m_l=-2, m_s=-1/2

II.

n=3, l=2, m_l=1, m_8=+1/2

III.

n=4, l=1, m_l=0, m_s=+1/2

IV.

n=3, l=1, m_l=1, m_s=-1/2

The correct order of their increasing energies will be:

(A)I < III < II < IV
(B)I < II < III < IV
(C)IV < II < III < I
(D)IV < III < II < I

Q167·ChemistrySingle correctJEE Main 2019

If the de Brogile wavelength of the electron in n

^{th}

Bohr orbit in a hydrogenic atom is equal to

1.5\pi a_0

(

a_0

is Bohr radius), then the value of n/z is :

(A)0.40
(B)1.50
(C)1.0
(D)0.75

Q168·ChemistrySingle correctJEE Main 2019

What is the work function of the metal if the light of wavelength 4000 Å generates photoelectrons of velocity

6\times10^5

ms

^{-1}

from it? (Mass of electron =

9\times10^{-31}

kg Velocity of light =

3\times10^8

ms

^{-1}

Planck's constant =

6.626\times10^{-34}

Js Charge of electron =

1.6\times10^{-19}

JeV

^{-1}

)

(A)0.9 eV
(B)3.1 eV
(C)2.1 eV
(D)4.0 eV

Q169·ChemistrySingle correctJEE Main 2019

The de Broglie wavelength (

\lambda

) associated with a photoelectron varies with the frequency (

\nu

) of the incident radiation as, [

\nu_{0}

is threshold frequency]:

(A) $\lambda \propto \dfrac{1}{(\nu - \nu_{0})}$
(B) $\lambda \propto \dfrac{1}{(\nu - \nu_{0})^{1/4}}$
(C) $\lambda \propto \dfrac{1}{(\nu - \nu_{0})^{3/2}}$
(D) $\lambda \propto \dfrac{1}{(\nu - \nu_{0})^{1/2}}$

Q170·ChemistrySingle correctJEE Main 2019

Heat treatment of muscular pain involves radiation of wavelength of about 900 nm. Which spectral line of H - atom is suitable for this purpose?

[R_H = 1\times10^5\ cm^{-1}, h = 6.6\times10^{-34}\ Js, c = 3\times10^8\ ms^{-1}]

(A)Paschen, $\infty \rightarrow 3$
(B)Paschen, $5 \rightarrow 3$
(C)Balmer, $\infty \rightarrow 2$
(D)Lyman, $\infty \rightarrow 1$

Q171·ChemistrySingle correctJEE Main 2019

Which of the graphs shown below does not represent the relationship between incident light and the electron ejected from metal surface?

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

Q172·ChemistrySingle correctJEE Main 2019

Which of the following combination of statements is true regarding the interpretation of the atomic orbitals? (1) An electron in an orbital of high angular momentum stays away from the nucleus than an electron in the orbital of lower angular momentum. (2) For a given value of the principal quantum number, the size of the orbit is inversely proportional to the azimuthal quantum number (3) According to wave mechanics, the ground state angular momentum is equal to

\frac{h}{2\pi}

(4) The plot of ψ Vs r for various azimuthal quantum numbers, shows peak shifting towards higher r value

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

Q173·ChemistrySingle correctJEE Main 2019

For emission line of atomic hydrogen from n

_{1}

= 8 to n

_{f}

= n, the plot of wave number (

\bar{v}

) against

\left(\frac{1}{n^{2}}\right)

will be(The Rydberg constant, R

_{H}

is in wave number unit)

(A)Linear with intercept - R $_{H}$
(B)Non linear
(C)Linear with slope R $_{H}$
(D)Linear with slope – R $_{H}$

Q174·ChemistrySingle correctJEE Advanced 2017

Answer by appropriately matching the information given in the three columns of the following table. The wave function

\psi_{n,l,m_{l}}

is a mathematical function whose value depends upon spherical polar coordinates

(r, \theta, \phi)

of the electron and characterized by the quantum numbers

n

,

l

and

m_{l}

. Here

r

is distance from nucleus,

\theta

is colatitude and

\phi

is azimuth. In the mathematical functions given in the Table, Z is atomic number and

a_{0}

is Bohr radius. For the given orbital in Column 1, the only CORRECT combination for any hydrogen-like species is

Column 1	Column 2	Column 3
(I) 1s orbital	(i) $\psi_{n,l,m_{l}} \propto \left(\frac{Z}{a_{0}}\right)^{\frac{3}{2}} e^{-\left(\frac{Zr}{a_{0}}\right)}$	(P)
(II) 2s orbital	(ii) One radial node	(Q) Probability density at nucleus $\propto \frac{1}{a_{0}^{3}}$
(III) 2p $_{z}$ orbital	(iii) $\psi_{n,l,m_{l}} \propto \left(\frac{Z}{a_{0}}\right)^{\frac{5}{2}} r e^{-\left(\frac{Zr}{2a_{0}}\right)} \cos\theta$	(R) Probability density is maximum at nucleus
(IV) 3d $_{z}^{2}$ orbital	(iv) $xy$ -plane is a nodal plane	(S) Energy needed to excite electron from $n = 2$ state to $n = 4$ state is $\frac{27}{32}$ times the energy needed to excite electron from $n = 2$ state to $n = 6$ state

(A)(IV) (iv) (R)
(B)(II) (ii) (P)
(C)(III) (iii) (P)
(D)(I) (ii) (S)

Q175·ChemistrySingle correctJEE Advanced 2017

Answer by appropriately matching the information given in the three columns of the following table. The wave function

\psi_{n,l,m_{l}}

is a mathematical function whose value depends upon spherical polar coordinates

(r, \theta, \phi)

of the electron and characterized by the quantum numbers

n

,

l

and

m_{l}

. Here

r

is distance from nucleus,

\theta

is colatitude and

\phi

is azimuth. In the mathematical functions given in the Table, Z is atomic number and

a_{0}

is Bohr radius. For hydrogen atom, the only CORRECT combination is

Column 1	Column 2	Column 3
(I) 1s orbital	(i) $\psi_{n,l,m_{l}} \propto \left(\frac{Z}{a_{0}}\right)^{\frac{3}{2}} e^{-\left(\frac{Zr}{a_{0}}\right)}$	(P)
(II) 2s orbital	(ii) One radial node	(Q) Probability density at nucleus $\propto \frac{1}{a_{0}^{3}}$
(III) 2p $_{z}$ orbital	(iii) $\psi_{n,l,m_{l}} \propto \left(\frac{Z}{a_{0}}\right)^{\frac{5}{2}} r e^{-\left(\frac{Zr}{2a_{0}}\right)} \cos\theta$	(R) Probability density is maximum at nucleus
(IV) 3d $_{z}^{2}$ orbital	(iv) $xy$ -plane is a nodal plane	(S) Energy needed to excite electron from $n = 2$ state to $n = 4$ state is $\frac{27}{32}$ times the energy needed to excite electron from $n = 2$ state to $n = 6$ state

(A)(I) (iv) (R)
(B)(I) (i) (P)
(C)(II) (i) (Q)
(D)(I) (i) (S)

Q176·ChemistrySingle correctJEE Advanced 2017

Answer by appropriately matching the information given in the three columns of the following table. The wave function

\psi_{n,l,m_{l}}

is a mathematical function whose value depends upon spherical polar coordinates

(r, \theta, \phi)

of the electron and characterized by the quantum numbers

n

,

l

and

m_{l}

. Here

r

is distance from nucleus,

\theta

is colatitude and

\phi

is azimuth. In the mathematical functions given in the Table, Z is atomic number and

a_{0}

is Bohr radius. For

He^{+}

ion, the only INCORRECT combination is

Column 1	Column 2	Column 3
(I) 1s orbital	(i) $\psi_{n,l,m_{l}} \propto \left(\frac{Z}{a_{0}}\right)^{\frac{3}{2}} e^{-\left(\frac{Zr}{a_{0}}\right)}$	(P)
(II) 2s orbital	(ii) One radial node	(Q) Probability density at nucleus $\propto \frac{1}{a_{0}^{3}}$
(III) 2p $_{z}$ orbital	(iii) $\psi_{n,l,m_{l}} \propto \left(\frac{Z}{a_{0}}\right)^{\frac{5}{2}} r e^{-\left(\frac{Zr}{2a_{0}}\right)} \cos\theta$	(R) Probability density is maximum at nucleus
(IV) 3d $_{z}^{2}$ orbital	(iv) $xy$ -plane is a nodal plane	(S) Energy needed to excite electron from $n = 2$ state to $n = 4$ state is $\frac{27}{32}$ times the energy needed to excite electron from $n = 2$ state to $n = 6$ state

(A)(II) (ii) (Q)
(B)(I) (i) (S)
(C)(I) (i) (R)
(D)(I) (iii) (R)

Q177·ChemistryMultiple correctJEE Advanced 2016

A plot of the number of neutrons (N) against the number of protons (P) of stable nuclei exhibits upward deviation from linearity for atomic number, Z > 20. For an unstable nucleus having N/P ratio less than 1, the possible mode(s) of decay is(are)

(A) $\beta^{-}$ -decay ( $\beta$ emission)
(B)orbital or K-electron capture
(C)neutron emission
(D) $\beta^{+}$ -decay (positron emission)

Q178·ChemistrySingle correctJEE Advanced 2016

P

is the probability of finding the 1s electron of hydrogen atom in a spherical shell of infinitesimal thickness,

dr

, at a distance

r

from the nucleus. The volume of this shell is

4\pi r^{2}dr

. The qualitative sketch of the dependence of

P

on

r

is

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

Q179·ChemistryIntegerJEE Advanced 2015

Not considering the electronic spin, the degeneracy of the second excited state (

n = 3

) of H atom is 9, while the degeneracy of the second excited state of

\mathrm{H^{-}}

is

Q180·ChemistryIntegerJEE Advanced 2014

In an atom, the total number of electrons having quantum numbers

n = 4

,

|m_l| = 1

and

m_s = -1/2

is

Q181·ChemistryIntegerJEE Advanced 2013

The atomic masses of He and Ne are 4 and 20 a.m.u., respectively. The value of the de Broglie wavelength of He gas at – 73

^{\circ}

C is "M" times that of the de Broglie wavelength of Ne at 727

^{\circ}

C. M is

Q182·ChemistryMultiple correctJEE Advanced 2013

In the nuclear transmutation

^{9}_{4}\mathrm{Be} + X \longrightarrow {}^{8}_{4}\mathrm{Be} + Y

(X, Y) is (are)

(A) $(\gamma, \mathrm{n})$
(B) $(\mathrm{p}, \mathrm{D})$
(C) $(\mathrm{n}, \mathrm{D})$
(D) $(\gamma, \mathrm{p})$

Atomic Structure — JEE Previous Year Questions

All 182 Atomic Structure questions

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