Tipping

Molecular structure of the propine.

Structure of the propino.

Methylacetylene, also called propyne, is an alkyne with the chemical formula CH₃C≡CH, and a molecular mass of 40.063 g/mol.

It is used in welding. It is a colorless gas with a characteristic odor, denser than air and can spread along the ground. Decomposes on heating and under the influence of pressure producing carbon monoxide and carbon dioxide, causing a fire or explosion hazard.

• Evaporation point: –23 °C
• Fusion point: –101.5 °C
• Water density: 0.68
• Solubility in water: 0,36 g/100 ml
• Steam pressure: 521 kPa (at 20 °C)
• Relative density of steam (air = 1): 1.4
• Explosive limits (% in volume in air): 1.7 - 11,7