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Arsenic
Metalloids · Group 15 · Period 4
Atomic properties
| Atomic number | 33 |
|---|---|
| Symbol | As |
| Standard atomic weight | 74.922 |
| Classification | Metalloids |
| Group | 15 |
| Period | 4 |
| Block | p-block |
| Electron configuration | [Ar] 3d10 4s2 4p3 |
| Electronegativity (Pauling) | 2.18 |
| Common oxidation states | +5, +3, -3 |
Physical properties
| Phase at 20 °C | Solid |
|---|---|
| Density | 5.727 g/cm³ |
| Melting point | 817 °C |
| Boiling point | 614 (subl.) °C |
| Discovered | Ancient |
| CAS number | — |