Answer to Question #193773 in Mechanics | Relativity for jay

Question

What are the quantum numbers for the electrons in the lithium

atom (Z = 3) when the atom is in its ground state?

Answer 1

Lithium has two 1s-electrons and one 2s-electron (1s²2s¹).

n is equal to the number of the subshell

l = 0 ... (n - 1) (for s-electrons l = 0)

m_l = -l ... +l

m_s = 1/2 or -1/2

Therefore,

Quantum numbers for 1s electron (1):

n = 1

l = 0

m_l = 0

m_s = 1/2

Quantum numbers for 1s electron (2):

n = 1

l = 0

m_l = 0

m_s = -1/2

Quantum numbers for 2s electron:

n = 2

l = 0

m_l = 0

m_s = 1/2