Propyne

Propyne, also called methylacetylene, is a three-carbon alkyne with the formula C₃H₄. Its carbon–carbon triple bond gives it characteristic alkyne chemistry.

Alkyne: A hydrocarbon containing at least one carbon–carbon triple bond. Propyne is the smallest alkyne with three carbon atoms.
Molecular formula: A notation giving the number of each type of atom in a molecule. C₃H₄ states the atom counts that distinguish propyne from other hydrocarbons.
MAPP gas: A fuel gas mixture historically sold as a portable alternative to acetylene. Commercial MAPP gas contained propyne as a combustible component.
Propene: A three-carbon alkene with formula C₃H₆ and one carbon–carbon double bond. Propene has the same carbon skeleton but a double bond and two additional hydrogens.
Terminal alkyne: An alkyne whose triple bond lies at the end of its carbon chain. Propyne’s triple bond ends in a hydrogen-bearing carbon.
Structural formula: A representation showing how atoms are connected within a molecule. The structure CH₃–C≡CH makes propyne’s triple bond position explicit.
Propadiene: A three-carbon cumulene with formula C₃H₄, also called allene. Propadiene shares propyne’s formula and can occur alongside it in fuel mixtures.
Propane: A saturated three-carbon alkane with formula C₃H₈. Propane shares propyne’s carbon count but lacks multiple bonds.
Acetylene: The two-carbon alkyne with formula C₂H₂, also called ethyne. Like acetylene, propyne has a terminal triple bond and undergoes alkyne reactions.
Carbon–carbon triple bond: A covalent bond in which two carbon atoms share three pairs of electrons. This bond is propyne’s defining structural feature.

Linked from 2 pages

DiacetyleneCompared with: It shows how adding carbon atoms differs from joining two triple-bond units.