Arsenic

33 germanium ← arsenic → selenium P ↑ As ↓ Sb periodic table General Name, Symbol, Number arsenic, As, 33 Chemical series metalloids Group, Period, Block 15, 4, p Appearance metallic gray Atomic mass 74.92160(2) g/mol Electron configuration [Ar] 3d10 4s2 4p3 Electrons per shell 2, 8, 18, 5 Physical properties Phase solid Density (near r.t.) 5.727 g·cm−3 Liquid density at m.p. 5.22 g·cm−3 Melting point 1090 K (817 °C, 1503& ...