Ethanoic acid has pKa value of 4.76 Trichloroethanoic acid has pKa value of 0.51 State which acid is stronger and suggest why it is stronger.

Answer 1

Ethanoic acid: CH3COOH

Trichloroethanoic acid: Cl3CCOOH

Trichloroethanoic acid is stronger as seen from the pKa value of 0.51 compared to 4.76. These convert to Ka values of ~3x10^-1 and 1.7x10^-5 respectively. Again, this shows that trichloro is stronger.

The reason it is stronger is because of the large electronegativity of chlorine. The three Cl atoms pull electrons toward them making the H of the COOH easier to dissociate.