30.2 g of glycerine (C3H8O3) are dissolved in...?

Question

30.2 g of glycerine (C3H8O3) are dissolved in
150 g of water. What is the boiling point of
the solution? (Kb of water = 0.515±C/m)
1. 103.52±C
2. 100.10±C
3. 1.13±C
4. 101.13±C
5. 0.104±C
02

Answer 1

Atomic weights: C=12 H=1 O=16 C3H8O3=92

Let glycerol be called G.

30.2gG/150gH2O x 1molG/92gG x 1000gH2O/1kgH2O = 2.19 mole G per kg H2O

2.19m x 0.515C/m = 1.13degC

100C + 1.13 = 101.13 degC (No. 4 is correct)