33As
Element 33
Arsenic
Metalloids
Arsenic is a chemical element with symbol As and atomic number 33.
Key data
- Atomic number
- 33
- Atomic mass
- 74.922 u
- Group / Period
- 15 / 4
- Block
- p-block
- Phase at STP
- Solid
- Density
- 5.727 g/cm³
- Melting point
- —
- Boiling point
- —
- Electron configuration
- [Ar] 3d10 4s2 4p3
Common uses
- •Wood preservative
- •Semiconductor dopant
- •Toxic histories
Discovery
Year: Known since antiquity
Discovered by: Bronze Age
Frequently asked questions
What is the atomic number of Arsenic?
Arsenic has atomic number 33. Its symbol is As and its atomic mass is 74.922 u.
What category of element is Arsenic?
Arsenic is classified as metalloids. It sits in group 15, period 4 of the periodic table.
What is Arsenic used for?
Common uses of Arsenic include: Wood preservative, Semiconductor dopant, Toxic histories.
When was Arsenic discovered?
Arsenic has been known since antiquity.
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