5
B
boron
10.81

General properties

Group
group 13
Period
period 2
Category
metalloids
Standard atomic weight
10.81
[10.806, 10.821]
Melting point
2349 K (2076 °C)
Boiling point
4200 K (3927 °C)
Phase at STP
solid

Additional properties

Block
p-block
Electron configuration
[He] 2s² 2p¹
Electrons per shell
2, 3
Electronegativity
2.04
Density
2.08 g/cm³
Oxidation states
−5, −1, 0, +1, +2, +3 (a mildly oxide)
CAS Number
7440-42-8