Ethyne boiling point

Acetylene (CH=CH, ethyne or ethine, melting point -81.5°C, boiling point -84°C) is an extremely reactive hydrocarbon that is moderately soluble in water or alcohol and is markedly soluble in acetone (300 volumes of acetylene dissolve in 1 volume of acetone at 176 psi, 1216 kPa). 

At room temperature, the first three members of the series (ethyne, propyne and butyne) are gases, the others are liquids. Branching, as in the other hydrocarbons, decreases the boiling point. 

Industrially they are produced in a continuous process by reacting hydrogen-containing silanes with ethyne in the presence of platinum compounds in high boiling point solvents. 

Alkynes are nonpolar and exhibit the same trends in boiling points and physical states as other hydrocarbons. The smallest alkyne, ethyne, is a gas. The combustion of ethyne when it is mixed with pure oxygen produces the intense heat of welding torches, as shown in Figure 2.11. As mentioned, the common name of ethyne is acetylene, so these welding torches are commonly called oxyacetylene torches. 

Alkynes have boiling points very similar to those of the corresponding alkenes and alkanes. Ethyne is nnnsnal in that it has no boiling point at atmospheric pressnre rather, it sublimes at 84°C. Propyne (b.p. -23.2°C) and 1-butyne (b.p. 8.1°C) are gases, whereas 2-butyne is barely a Uquid (b.p. 27°C) at room temperature. The medium-sized alkynes are distillable liquids. 

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