NEET Chemistry Structure of Atom Questions Solved

Which of the following sets of quantum numbers represent an impossible arrangement -

n l m s

(A) 3 2 -2 (+)1/2

(B) 4 0 0 (-)1/2

(D) 5 3 0 (-)1/2

#Quantum Numbers

Difficulty Level:

(a)
10%
(b)
23%
(c)
60%
(d)
8%

How many unpaired electrons are present in Ni²⁺ cation (atomic number = 28)

(A) 0

(B) 2

(D) 6

#AUFBAU

(B) Two unpaired electrons are present in Ni⁺⁺ (z=28) cation

Difficulty Level:

(a)
17%
(b)
55%
(c)
23%
(d)
7%

Correct set of four quantum numbers for the outermost electron of rubidium (Z=37) is:

(A) 5, 0, 0, 1/2

(B) 5, 1, 0, 1/2

(D) 6, 0, 0, 1/2

#Quantum Numbers

(A) Its configuration is 5s¹

Difficulty Level:

(a)
62%
(b)
17%
(c)
16%
(d)
7%

Number of unparired electrons in 1S² 2S² 2P³ is -

1. 2

2. 0

3. 3

4. 1

#Hunds Rule

Difficulty Level:

(a)
5%
(b)
6%
(c)
84%
(d)
7%

The quantum numbers of four electrons are given below.

n $l$ m s

(1) Electron 1 3 0 0 -1/2

(2) Electron 2 4 0 1 1/2

(3) Electron 3 3 2 0 1/2

(4) Electron 4 3 1 0 -1/2

The correct order of decreasing energy of these electrons is -

(A) Electron 3 > Electron 1 > Electron 4> Electron 2

(B) Electron 4> Electron 2 > Electron 3 > Electron 1

(D) Electron 2 > Electron 4 > Electron 3 > Electron 1

#Quantum Numbers

Difficulty Level:

(a)
7%
(b)
18%
(c)
60%
(d)
16%

Which type of radiation is not emitted by the electronic structure of atoms:

(A) Ultraviolet light

(B) X-rays

(D) y-rays

#EMT Radiation

(D) y-rays emission occurs due to radioactive change, a nuclear phenomenon.

Difficulty Level:

(a)
15%
(b)
13%
(c)
22%
(d)
52%

Of the following transitions in hydrogen atom, the one which gives an absorption line of lowest frequency is

(A) n=1 to n=2

(B) n=3 to n=8

(D) n=8 to n=3

#Hydrogen Spectra

(B) Absorption line in the spectra arise when energy is absorbed i.e., electron shifts from lower to higher orbit, out of A and B, B will have the lowest frequency as this falls in the Paschen series.

Difficulty Level:

(a)
32%
(b)
31%
(c)
23%
(d)
16%

If uncertainty in the position of an electron is zero the uncertainty in its momentum will be

(A) < h/4 $π$

(B) > h/4 $π$

(D) infinite

#Heisenberg Uncertainity Principle

(D) $∆$ x x $∆$ p $\geq h / 4 π$

if $∆$ x = 0, then $∆$ p will be infinite

Difficulty Level:

(a)
9%
(b)
19%
(c)
30%
(d)
45%

The maximum number of atomic orbitals associated with a principal quantum number 5 is

(A)9

(B)12

(D) 25

#Quantum Numbers

(D) The number of orbitals in a principle shell is n²= 5²=25

Difficulty Level:

(a)
15%
(b)
12%
(c)
16%
(d)
59%

The de Broglie wavelength of electron of He⁺ ion is 3.329Å. If the photon emitted upon de-excitation of this He⁺ ion is made to hit H atom in its ground state so as to liberate electron from it, what will be the de Broglie's wavelength of photoelectron ?

(A) 0.1518 Å

(B) 6.1518 Å

(D) 4.1218 Å