chemistry

ALKALI AND ALKALINE EARTH METALS

Alkali metal

Z	Element	No. of electrons/shell	Electron configuration
3	lithium	2, 1	[He] 2s1
11	sodium	2, 8, 1	[Ne] 3s1
19	potassium	2, 8, 8, 1	[Ar] 4s1
37	rubidium	2, 8, 18, 8, 1	[Kr] 5s1
55	caesium	2, 8, 18, 18, 8, 1	[Xe] 6s1
87	francium	2, 8, 18, 32, 18, 8, 1	[Rn] 7s1

 Alkaline earth metal

Z	Element	No. of electrons/shell	Electron configuration
4	beryllium	2, 2	[He] 2s2
12	magnesium	2, 8, 2	[Ne] 3s2
20	calcium	2, 8, 8, 2	[Ar] 4s2
38	strontium	2, 8, 18, 8, 2	[Kr] 5s2
56	barium	2, 8, 18, 18, 8, 2	[Xe] 6s2
88	radium	2, 8, 18, 32, 18, 8, 2	[Rn] 7s2