A certain liquid has a normal freezing point of and a freezing point depression constant . Calculate the freezing point of a solution made of of iron(III) chloride () dissolved in of . Round your answer to significant digits.

The question is incomplete, the complete question is:

A certain liquid X has a normal freezing point of and a freezing point depression constant . Calculate the freezing point of a solution made of 81.1 g of iron(III) chloride () dissolved in 850. g of X. Round your answer to significant digits.

The freezing point of the solution is

Explanation:

Depression in the freezing point is defined as the difference between the freezing point of the pure solvent and the freezing point of the solution.

The expression for the calculation of depression in freezing point is:

OR

......(1)

where,

Freezing point of pure solvent =

Freezing point of solution =

i = Vant Hoff factor = 4 (for iron (III) chloride as 4 ions are produced in the reaction)

= freezing point depression constant =

= Given mass of solute (iron (III) chloride) = 81.1 g

= Molar mass of solute (iron (III) chloride) = 162.2 g/mol

= Mass of solvent (X) = 850. g

Putting values in equation 1, we get:

Hence, the freezing point of the solution is