Question

Arrange the following orbitals in decreasing order of energy ? 

(A) n = 3, l = 0, m = 0 

(B) n = 4, l = 0, m = 0 

(C) n = 3, l = 1, m = 0 

(D) n = 3, l = 2, m = 1 

The correct option for the order is : 

(1) B > D > C > A 

(2) D > B > C > A

(3) A > C > B > D

(4) D > B > A >C

Answer 1

(2) D > B > C > A

(A) n = 3; l = 0; m = 0 ; 3s orbital 

(B) n = 4; l = 0; m = 0 ; 4s orbital 

(C) n = 3; l = 1; m = 0 ; 3p orbital 

(D) n = 3; l = 2; m = 0 ; 3d orbital 

As per Hund’s rule energy is given by (n+l) value. If value of (n+l) remains same then energy is given by n only.