JEE Main 2026 · 5 Apr · Shift 1 · Chemistry Q53

ChemistrySingle correct+4 / -1Question 53 of 75

Identify the correct statements from the following :

A. Heisenberg uncertainty principle is applicable to electrons.

B. The size of $2p_x$ orbital is less than the size of $3p_x$ orbital.

C. The energy of 2s orbital of H atom is equal to the energy of 2s orbital of Li.

D. The electronic configuration of Cr is $[\mathrm{Ar}]\,3d^54s^1$

Choose the correct answer from the options given below:

A, B and C Only

A, B and D Only

B, C and D Only

A, C and D Only

Answer and worked solution

Official answer: B

Each statement.

A: The uncertainty principle applies to all microscopic particles, electrons included. True.
B: Orbital size grows with n, so 2p is smaller than 3p. True.
C: In H, energy depends only on n. In Li, the 2s energy depends on the effective nuclear charge and is different. False.
D: Cr is $[\mathrm{Ar}]\,3d^54s^1$ , from half-filled stability. True.

Correct: A, B and D.

(B)

JEE Main 2026 · 5 Apr · Shift 1, Chemistry question 53