Question

The electrons identified by quantum numbers n and l,
A. n = 4, l = 1
B. n = 4, l = 0
C. n = 3, l = 2
D. n = 3, l = 1 can be placed in order of increasing energy, from the lowest to highest as

• A. D < B < C < A
• B. B < D < A < C
• C. A < C < B < D
• D. C < A < D < B

Answer 1

The correct option is A D < B < C < A

$n=4,l=1\Rightarrow 4p$

$n=4,l=0\Rightarrow 4s$

$n=3,l=2\Rightarrow 3d$

$n=3,l=1\Rightarrow 3p$

$3p<4s<3d<4p$