Consider the ground state of chromium atom (Z = 24). How many electrons are with azimuthal quantum number l = 1 and l = 2 respectively?

Azimuthal Quantum Number Electrons in Chromium | JEE Mains PYQ | Structure of Atom

Q. Consider the ground state of chromium atom (Z = 24). How many electrons are with azimuthal quantum number l = 1 and l = 2 respectively?

A. 16 and 5

B. 12 and 5

C. 12 and 4

D. 16 and 4

Explanation

Step 1: Write ground state electronic configuration of chromium

Chromium (Z = 24):
1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s¹

Step 2: Count electrons with l = 1 (p-orbitals)

p-orbitals have l = 1
2p⁶ + 3p⁶ = 12 electrons

Step 3: Count electrons with l = 2 (d-orbitals)

d-orbitals have l = 2
3d⁵ = 5 electrons

Correct Answer = 12 and 5

Previous Year Questions – Structure of Atom

The extra stability of half-filled subshell is due to :

Which one of the following about an electron occupying the 1s orbital in a hydrogen atom is incorrect?

For electrons in ‘2s’ and ‘2p’ orbitals, the orbital angular momentum values, respectively, are :

10 mL of gaseous hydrocarbon on combustion gives 40 mL of CO₂(g) and 50 mL of water vapour. Total number of carbon and hydrogen atoms in the hydrocarbon is ______ .

Mass of methane required to produce 22 g of CO₂ after complete combustion is ______ g.

JEE Mains Full Study Material

Updated for JEE Main 2026: This PYQ is important for JEE Mains, JEE Advanced and other competitive exams. Practice more questions from this chapter.