Why is ethyne () significantly more acidic than ethane ()? — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

The acidity of hydrocarbons depends on the hybridization of the carbon atom. The $sp$ hybridized carbon in ethyne has 50% s-character, making it highly electronegative. It exerts a strong $-I$ effect, stabilizing the negative charge on the conjugate base ($HC\equiv C^-$) better than an $sp^3$ carbon.