Chemistry · d and f Block Elements

JEE Main 2025 — 4 April, Evening Shift — Question 2

Consider the ground state of chromium atom ( $Z=$ 24). How many electrons are with Azimuthal quantum number $\mathrm{I}=1$ and $\mathrm{I}=2$ respectively?

Option A:
16 and 4
Option B:
12 and 4
Option C:
12 and 5
Correct
Option D:
16 and 5

Answer: C

Step-by-step solution

$\mathrm{Cr}[24]: 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{5}$

$I = 1$ : p-orbital: $\mathrm{n}_{\mathrm{e}}=12$

$\mathrm{I}=2$ : d-orbital : $\mathrm{n}_{\mathrm{e}}=5$

Answer key and solution verified before publishing.

Practise d and f Block Elements

Start with this question, then two more from the same chapter — with a tutor that explains every step. Free.

Solve a similar one free

Exam: JEE Main 2025
Paper: 4 April, Evening Shift
Subject: Chemistry
Chapter: d and f Block Elements
Topic: Properties of compounds of 3d Series elements + Comparison between 3d, 4d, 5d

The incorrect relationship in the following pairs in relation to ionisation enthalpies is

Answer: C

Step-by-step solution

Practise d and f Block Elements

More d and f Block Elements questions from this paper