Question

How many electrons in an atom may have the following quantum numbers?

(a) n = 4; m_s = – 1/2

(b) n = 3, l = 0.

Answer 1

(a) For n = 4 1 

Total number of electrons = 2n² = 2 x 16 = 32 

Half out of these will have ms = – 1/2

Total electrons with m_s (- 1/2) = 16. 

(b) For n = 3 

l = 0; m₁ = 0, m_s = + 1/2 – 1/2 (two e^-).