Question

5 gm of a substance when dissolved in 50 gm water lowers the freezing point by 1.2°c. Calculate molecular weight of the substance; if kf of water = 1.86 k kg /mole.​

Answer 1

Answer:

By dissolving 5 g substance in 50 g of water, the decrease in freezing point is 1.2∘C. The gram molal depression is 1.85∘C. The molecular weight of substance is. m=1000×1.85×51.2×50=154.2.