Question

Why are alkynes more acidic than alkanes and alkenes?

Answer 1

Alkynes

• Alkynes are also unsaturated hydrocarbons.
• They contain at least one triple bond between two carbon atoms.
• Unsaturated hydrocarbons contain carbon-carbon multiple bonds – double bonds, triple bonds, or both.
• Saturated hydrocarbons contain carbon-carbon and carbon-hydrogen single bonds.

Acidic nature of alkyne

• The hybridization of carbon atom in alkyne is $sp$, alkene is $s{p}^2$, and alkane is $s{p}^3$.
• The s character in alkyne is $50\%$.
• $sp$ carbon atoms are more electronegative than $s{p}^2$ carbon atoms, which are in turn more electronegative than $s{p}^3$ carbon atoms.
• The more electronegative carbon atom attracts the shared pair of electrons more strongly.
• So, the acidic nature of alkyne is more compared to alkane and alkene.