33AsArsenic74.9215956[Ar] 3d¹⁰ 4s² 4p³
metalloid
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.
A stylized shell model. Electrons are quantum objects, not particles following these literal paths. Sizes and motion are illustrative.
Electrons by shell
Electron configuration
3d10
4s2
4p3
18 is the [Ar] core total across three shells.
At a glance
- Atomic number
- 33
- Atomic mass
- 74.921596 u
- Phase
- Solid
- Density
- 5.727 g/cm³
- Melting point
- Unavailable
- Boiling point
- Unavailable
- First ionization energy
- 947 kJ/mol
- Electronegativity
- 2.18
- Electron affinity
- 77.65 kJ/mol
- Molar heat capacity
- 24.64 J/(mol·K)
- Period
- 4
- Appearance
- metallic grey
Conditions and isotopes affect measured properties. Some properties of short-lived elements are predicted. Electronegativity uses the Pauling scale.
Keep exploring
Explore the stories, imagery, and reference data in more depth. Properties with no value in the reference are marked unavailable.