Question

What weight of glycerol should be added to 600 g of water in order to lower its freezing point by $10ºC$?

($K_{f} = 1.8ºCm^{- 1}$)

• A. 496 g
• B. 297 g
• C. 310 g
• D. 426 g

Answer 1

Answer: (B)

297 g

Answer 2

$\Delta T_{f} = k_{f} \times m = \frac{k_{f} \times W_{2} \times 1000}{M_{2} \times W_{1}}$

$W_{2} = \frac{10 \times 92 \times 600}{1.86 \times 1000} = 296.77g$