NEET Practice Questions - Chemistry - Structure of Atom

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

(C)  3   2   -3   (+)1/2

(D)  5   3   0   (-)1/2

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

(A) 0

(B) 2

(C) 4

(D) 6

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

(C) 5, 1, 1, 1/2

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

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

1. 2

2. 0

3. 3

4. 1

The quantum numbers of four electrons are given below.

                                  n            $\mathcal{l}$           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

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

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

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

(A) Ultraviolet light

(B) X-rays

(C) Visible light

(D) y-rays

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

(C) n=2 to n=1

(D) n=8 to n=3

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

(A) < h/4$\mathrm{\pi }$

(B) > h/4$\mathrm{\pi }$

(C) zero

(D) infinite

Which has highest e/m ratio:

1. He²⁺

2. H⁺

3. H¹⁺

4. H

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

(A)9

(B)12

(C) 16

(D) 25