Arsenic (As) — Element 33

33 As 74.922

Arsenic

Element 33 · 74.922 u · p-block

metalloid

A notorious poison throughout history. Used in semiconductors and wood preservatives. Exists in grey, yellow, and black forms.

Phase (STP)

Solid

Melting Point

817 °C

Boiling Point

614 °C

Density

5.776 g/cm³

Electronegativity

2.18

Atomic Radius

115 pm

Ionization Energy

947 kJ/mol

Electron Affinity

78 kJ/mol

Discovered

Ancient · Known since antiquity

Electron Configuration

[Ar] 3d10 4s2 4p3