Chemistry molar mass help

Question

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  of quinine is dissolved in  of cyclohexane, the freezing point of the solution is lowered by  Look up the freezing point and  constant for cyclohexane in the . 

Calculate the molar mass of quinine.

Answer 1

Freezing pt cyclohexane = 6.5 C (note: don’t need this to answer this question)

Kf = 20.1

ΔT = imK

ΔT = change in temp = 2.44 deg

i = vant Hoff factor = 1 for quinine, a non electrolyte

m = molal = mol solute/kg solvent = ?

K = 20.1

m = 2.44/(1)(20.1) = 0.121 moles/kg

0.121 mol/kg x 0.025 kg = 0.00303 moles

molar mass = 0.950 g/0.00303 mole = 314 g/mol