Question

atch the following aqueous solutions with the appropriate letter from the column on the right. fill in the blank 1 A 1. 0.20 m NiSO4 A. Highest boiling point fill in the blank 2 B 2. 0.19 m NH4I B. Second highest boiling point fill in the blank 3 C 3. 0.17 m NH4NO3 C. Third highest boiling point fill in the blank 4 D 4. 0.43 m Urea(nonelectrolyte) D. Lowest boiling point

Answer 1

Highest boiling point - 0.43 m Urea

Second highest boiling point - 0.20 m NiSO4

Third highest boiling point - 0.19 m NH4I

Lowest boiling point - 0.17 m NH4NO3

Step-by-step explanation:

We know that;

ΔT = kb m i

Where;

ΔT = boiling point elevation

kb = boiling point constant

m = molality of the solution

i = Van't Hoff factor

For NiSO4 , NH4I and NH4NO3 , the Van't Hoff factor, i = 2

But for Urea, the Van't Hoff factor, i = 1

We also have to consider both the values of the molality and Van't Hoff factor , knowing that a higher molality and a higher Van't Hoff factor leads to a higher ΔT and consequently a higher boiling point.

This facts above account for the arrangement of substances shown in the answer.