JEE Main 2025 Jan 23 Shift 2, Chemistry Q9: Quantum Numbers

JEE Main2025Jan 23, Shift 2Chemistry

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

Solution

For principal quantum number $n$ , the azimuthal number $l$ runs from $0$ to $n - 1$ , and for each $l$ the magnetic number $m_{l}$ takes $2 l + 1$ values.

Total orbitals $= l = 0 \sum n - 1 (2 l + 1) = n^{2}$ . Statement I is correct.

The orientations of orbitals within a subshell are labelled by $m_{l} = - l, - l + 1, \dots, 0, \dots, + l$ . Statement II is correct.

$∴$ Both statements are true.

Concept behind this question

Quantum NumbersNotes, formulas and examples →

Practice more Chemistry

Concept-wise practice with instant solutions on Fundamenthol.

Start practicing →

JEE Main 2025 Jan 23 Shift 2, Chemistry Q9: Quantum Numbers

Concept behind this question

More previous year questions on Quantum Numbers

Practice more Chemistry