Physical properties
Phase solid
Melting point 494 K (221 °C, 430 °F)
Boiling point 958 K (685 °C, 1265 °F)
Density near r.t. gray: 4.81 g/cm3
alpha: 4.39 g/cm3
vitreous: 4.28 g/cm3
when liquid, at m.p. 3.99 g/cm3
Critical point 1766 K, 27.2 MPa
Heat of fusion gray: 6.69 kJ/mol
Heat of vaporization 95.48 kJ/mol
Molar heat capacity 25.363 J/(mol·K)
vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 500 552 617 704 813 958