The cells of a tomato contain mostly an aqueous solution of sugar and other substances. If a typical tomato freezes at -2.5 °C, what is the molality of the sugar in solution? (Hint: sugar is a covalent compound, it does not dissociate in water)
We can solve this problem by using the freezing point depression formula:
ΔT = Kf * m * i
Where:
ΔT is the temperature difference between the freezing point of the pure solvent (water) and the solution. In this case it is (0 °C - -2.5 °C = 2.5 °C).
Kf is the cryoscopic constant, for water it is 1.853 °C*kg/mol.
m is the molality.
i is the van't Hoff factor, as sugar does not dissociate in water, it has a value of 1.
