Question

Assertion : The outer electronic configuration of Cr and Cu are `3d^(5) 4s^(1) ` and `3d^(10) 4s^(1)` respectively .
Reason : Electrons are filled in orbitals in order of increasing energies given by (n+l) rule.
A. if both assertion and reason are correct and reason is correct explanation for assertion .
B. If both assertion and reason are correct but reason in not correct explanation for assertion.
C. If assertion is correct but reason is incorrect.
D. If both assertion and reason are incorrect.

Answer 1

Correct Answer - B
Correct explanation. This is because completley filled and half-filled electronic configurations impart extra stability due to symmetrical distribution of electrons and more exchange energy.