Kf value cyclohexane 208 Cm Freezing point 659 C Menthol i

Kf value cyclohexane = 20.8 C/m

Freezing point = 6.59 C

Menthol is a crystalline substance with a peppermint taste and odor. When 1.07 g of menthol is dissolved in 25.0 g of cyclohexane, the freezing point of the solution is lowered by 5.71 degree C. The freezing point and Kf constant for cyclohexane can be found here. Calculate the molar mass of menthol.

Solution

Depression in freezing point = iKfm 5.71 = 1 x 20.8 x [(1.07/Molar mass)/0.025] Molar mass = 155.90 g/mol