Which of the following carbanions exhibits the highest thermodynamic stability based on the hybridiz — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

The stability of a carbanion increases with the s-character of the orbital holding the negative charge. The ethynyl carbanion is $sp$ hybridized (50% s-character), holding the electrons closest to the nucleus, making it exceptionally stable compared to $sp^2$ or $sp^3$ carbanions.