Polarizability/Electronegativity and Acidity

[Alex Dayrit 3B]

Why is a molecule more acidic when it is more polarized or has high electronegativity?

[Iman Gauhar 3E]

A molecule is more acidic when it is highly electronegative because having a stable anion is a property of a strong acid. The anion is more stable when there are highly electronegative atom(s) because the highly electronegative atom(s) delocalize and stabilize the negative charge after the proton is donated.

[Andrew Nguyen 1E]

Hello,

Molecules that are more polarized (or have a highly electronegative atom) have a more exposed O-H bond. The electrongative atom pulls electron density away from the O-H bond, making it easier for the molecule to be deprotonated, thus making it a better acid. The resulting conjugate base (the anion) is more stable without the H+ as well, also demonstrating why stronger acids have more electronegative atoms (O, Cl, etc.) attached.