a. Out of 0.1 molal aqueous solution of glucose and 0.1 molal aqueous solution of KCl, which one will have higher boiling point and why?

b. Predict whether van’t Hoff factor, (i) is less than one or greater than one in the following :

i. CH₃COOH dissolved in water

ii. CH₃COOH dissolved in benzene

(a) 0.1 molal aqueous solution of KCl will have higher boiling point because KCl dissociates in aqueous solution to give K⁺ and Cl^- ions, but glucose does not dissociate and elevation in boiling point is a colligative property, i.e., it depends upon the no. of atoms. So, KCl will have higher B.P.

(b)

i. i>1

When CH₃COOH is dissolved in water, it dissociates into ions. In case of dissociation, van’t Hoff factor(i) is greater than 1

ii. i<1

When CH₃COOH is dissolved in benzene, it associates to form a dimer. In case of association, van’t Hoff factor(i) is less than 1