Phosphorus vs Arsenic
| Property | P Phosphorus | As Arsenic |
|---|---|---|
| Atomic number | 15 | 33 |
| Symbol | P | As |
| Name | Phosphorus | Arsenic |
| Category | nonmetal | metalloid |
| Standard Atomic Weight | 30.973762 u | 74.921595 u |
| Period | 3 | 4 |
| Group | 15 | 15 |
| Block | p | p |
| Phase at STP | solid | solid |
| Electron configuration | [Ne]3s23p3 | [Ar]4s23d104p3 |
| Oxidation states | [-3, -2, -1, 0, 1, 2, 3, 4, 5] | [-3, -2, -1, 0, 1, 2, 3, 4, 5] |
| Electronegativity (Pauling) | 2.19 | 2.18 |
| Electron affinity | 0.7466 eV | 0.81 eV |
| Density | 1820 kg/m³ | 5776 kg/m³ |
| Melting point | 44.15 °C | 816.85 °C |
| Boiling point | 280.5 °C | 613.85 °C |
| Discovery year | 1669 | 1250 |