33 As 74.922

Arsenic

metalloid

Properties

Atomic number
33
Atomic mass
74.922 u
Category
metalloid
Group
15
Period
4
Block
p-block
State (room temp)
Solid
Outer-shell electrons
5
Electronegativity
2.18 (Pauling)
Density
5.727 g/cm³
Melting point
Boiling point

Electron configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p³

Noble-gas shorthand: [Ar] 3d¹⁰ 4s² 4p³

Electrons per shell: 2, 8, 18, 5 — that's 5 in the outermost shell.

See how electron configuration is built →

As
Bohr model — outer-shell electrons in blue

About Arsenic

Arsenic is a chemical element with symbol As and atomic number 33. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. Arsenic is a metalloid.

Position in the periodic table

Open the interactive periodic table →

Data compiled from Wikipedia, PubChem, and IUPAC. Source.