Atomic Element Z = 33 • Metalloid
Arsenic (As) — Atomic Data, Electron Shells & Reactions
Arsenic (symbol As, atomic number 33) has a standard atomic weight of 74.922 u and ground-state configuration [Ar] 3d10 4s2 4p3.
Atomic Number (Z)
33
IUPAC Symbol
As
Standard Atomic Weight
74.922 g/mol
Period / Group / Block
4 / 15 / p-block
Condensed Electron Config
[Ar] 3d10 4s2 4p3
Full Subshell Config
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p3
Principal Shell Occupancy
[2, 8, 18, 5]
Pauling Electronegativity
2.18
First Ionization Energy
947 kJ/mol
Covalent Radius
119 pm
Melting Point
1090 K (816.85 °C)
Boiling Point
887 K (613.85 °C)
Density
5.776 g/cm³
Oxidation States
+5, +3, -3
As (Z=33) — Valence shell highlighted in vermilion