Phase gas Density (0 °C, 101.325 kPa) 3.2 g/L Liquid density at b.p. 1.5625[1] g·cm−3 Melting point 171.6 K, -101.5 °C, -150.7 °F Boiling point 239.11 K, -34.04 °C, -29.27 °F Critical point 416.9 K, 7.991 MPa Heat of fusion (Cl2) 6.406 kJ·mol−1 Heat of vaporization (Cl2) 20.41 kJ·mol−1 Molar heat capacity (Cl2) 33.949 J·mol−1·K−1