When 74.8g of alanine C3H7NO2 are dissolved in 1450.g of a certain mystery liquid X, the freezing point of the solution is 8.30°C less than the freezing point of pure X. Calculate the mass of potassium bromide that must be dissolved in the same mass of X to produce the same depression in freezing point. The van't Hoff factor =i1.72 for potassium bromide in X.

The mass of potassium bromide that must be dissolved in the same mass of X to produce the same depression in freezing point is 58.2 grams

Explanation:

Depression in freezing point is given by:

= Depression in freezing point

i= vant hoff factor = 1 (for non electrolyte)

= freezing point constant =  

m= molality =

Let Mass of solute (KBr) = x g

Thus the mass of potassium bromide that must be dissolved in the same mass of X to produce the same depression in freezing point is 58.2 grams