Increasing order of ΔTf(
depression in freezing point )
is :
Acetic acid <
TriCHMloroaceic acid <
Trifluoroacetic acid
Due to high electronegativity of F
atom, it exerts greater -I(
inductive effect)
. Consequenctly, III
is the strongest acid and I
is the weakest acid. Hence III
ionized to the largest extent and ionizes to the minimum extent to give ions in their solutions in water. ΔTf
is directly proportional to the number of ions. Hence, the above order.