trichloroacetic acid vs acetic acid

[OishiBhattacharya2K]

Can somebody clarify why trichloroacetic acid is a stronger acid than acetic acid and why this is important? I was a bit confused during that part of the lecture.

[Alexandra Gill]

Trichloroacetic acid is a stronger acid because it has more Chlorines, which are very electronegative and therefore draw electron density away from the carboxyl end of the molecule, which weakens the bond between O and H. Since the OH bond in trichloroacetic acid is weaker than in acetic acid, it will give away the proton more easily, making it a stronger acid.

[Naman Jain 3F]

The additional amount of chlorines in trichloroacetic acid results in a larger delocalization of the electrons and stabilization of the negative charge on the oxygen bonded to the hydrogen atom. This results in a weaker bond between the oxygen and hydrogen, making it easier for the compound to lose an H+ proton, making it a stronger acid effectively. Acetic acid doesn't do this as it has hydrogens instead of chlorines which don't have a strong electronegativity.

[Omar Alami 3H]

Hi,

The biggest and most applicable difference between the two is that trichloroacetic acid has 3 chlorines on one end as compared to the 3 hydrogens on the end for acetic acid. This difference means that since trichloroacetic acid has a greater electron induction to the side of the highly electronegative Chlorines, the bond between the O-H gets pulled more towards the O and causes the bond between the two to weaken. By the bond being weaker, a proton can be lost more easily, making trichloroacetic acid more acidic.