Question

Out of trifluoroacetic acid and acetic acid which one should lower the freezing point of water to a greater extent? Why?

Answer 1

Fluorine is more electronegative than carbon and has  stronger -I effect. trifluoroacetic acid is stronger than acetic acid. Hence, trifluoroacetic acid ionizes more than acetic acid. More the number of ions produced, more is the depression in freezing point (lowers freezing point). Thus, the depression in freezing point is more for the trifluoroacetic acid and less for acetic acid.