Question

Read the following statements and mark the incorrect statement.

• A. No two electrons in an atom can have all the four quantum numbers same.
• B. All the orbitals in a subshell are first occupied singly with parallel spins.
• C. The outer electronic configuration of chromium atom is $3d^{4}4s^2$
• D. Lyman series of hydrogen spectrum lies in ultraviolet region.

Answer 1

The correct option is C The outer electronic configuration of chromium atom is $3d^{4}4s^2$

A. No two electrons in an atom can have all the four quantum numbers same- Pauli's exclusion principle.

B. All the orbitals in a subshell are first occupied singly with parallel spins- Hund's rule of maximum multiplicity.

C. The outer electronic configuration of chromium atom is $3d^{5}4s^1$ due to the extra stability of half-filled configuration.

D. Lyman series of hydrogen spectrum is from higher energy orbit to first orbit and it lies in ultraviolet region.