Nuclear & Particle Physics - Electron Configuration

The ground state configuration of a neutral sodium atom (Z = 11) is
   
A. 1s² 2s² 2p⁵ 3s²
B. 1s² 2s³ 2p⁶
C. 1s² 2s² 2p⁶ 3s   
D. 1s² 2s² 2p⁶ 3p
E. 1s² 2s² 2p⁵

(GR9277 #58)

Solution:

Z = 11 → 1s² 2s² 2p⁶ 3s¹

Answer: C


Note:

Electron configuration:

	l = 0	l = 1	l = 2	l = 3	# of electrons
n = 1	1s2				2
n = 2	2s2	2p6			8
n = 3	3s2	3p6	3d10		18
n = 4	4s2	4p6	4d10	4f14	32