Chemical, physical and thermal properties of Acetylene (Ethyne) - C2H2 :
| Molecular Weight | 26.04 |
| Specific Gravity | 0.90 |
| Specific Volume (ft3/lb, m3/kg) | 14.9, 0.93 |
| Density of liquid at atmospheric pressure (lb/ft3, kg/m3) | 43.0, 693 |
| Absolute Viscosity (lbm/ft s, centipoises) | 6.72 10-6, 0.01 |
| Sound velocity in gas (m/s) | 343 |
| Specific Heat - cp - (Btu/lboF or cal/goC, J/kgK) | 0.40, 1674 |
| Specific Heat Ratio - cp/cv | 1.25 |
| Gas constant - R - (ft lb/lboR, J/kgoC) | 59.3, 319 |
| Thermal Conductivity (Btu/hr ft oF, W/moC) | 0.014, 0.024 |
| Boiling Point - saturation pressure 14.7 psia and 760 mm Hg - (oF, oC) | -103, -75 |
| Latent Heat of Evaporation at boiling point (Btu/lb, J/kg) | 264, 614000 |
| Freezing or Melting Point at 1 atm (oF, oC) | -116, -82.2 |
| Latent Heat of Fusion (Btu/lb, J/kg) | 23, 53500 |
| Critical Temperature (oF, oC) | 97.1, 36.2 |
| Critical Pressure (psia, MN/m2) | 907, 6.25 |
| Flammable | yes |
| Heat of combustion (Btu/ft3, Btu/lb, kJ/kg) | 1450, 21600, 50200 |
- values at 25oC (77oF, 298 K) and atmospheric pressure
