Question

1) The boiling point of an aqueous solution is 101.98 ∘C. What is the freezing point? Consult the table of colligative constants.

freezing point:   °C

2)

Quinine is a natural product extracted from the bark of the cinchona tree, which is native to South America. Quinine is used as an antimalarial agent.

When 0.829 g of quinine is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 2.13 ∘C. Look up the freezing point and Kf constant for cyclohexane in the Colligative Constants table.

Calculate the molar mass of quinine.

molar mass:

g/mol

3)

If a 0.770 m aqueous solution freezes at −2.30 ∘C, what is the van't Hoff factor, i, of the solute?

Consult the table of K_f values.

i=

Answer 1