Functional GroupsMedium

Relative acidity

Which is more acidic: acetic acid (CH₃COOH) or trichloroacetic acid (CCl₃COOH)?

Given data

CH₃COOH vs CCl₃COOH

Review the theory: Gruppi Funzionali

Steps

0 / 1

An acid is stronger the more stable its conjugate base. So I compare the effect of the substituents on the carboxylate: electron-withdrawing groups (like Cl atoms, inductive effect −I) spread out and stabilize the negative charge, making the acid stronger.
Write your working — the numerical result must appear in the text

Full worked solution

An acid is stronger the more stable its conjugate base. So I compare the effect of the substituents on the carboxylate: electron-withdrawing groups (like Cl atoms, inductive effect −I) spread out and stabilize the negative charge, making the acid stronger.
Trichloroacetic acid (pKa ≈ 0.66 vs 4.76): the three Cl withdraw electrons (inductive effect −I) and stabilize the carboxylate → a much stronger acid.

Result:Trichloroacetic acid (pKa ≈ 0.66)