The Freezing Point of Pure Benzene Was Measured as 5

Multiple Choice

The freezing point of pure benzene was measured as 5.49 °C.With the same benzene and the same equipment,the freezing point of a solution containing 6.60 g of an unknown molecular compound in 140 g of benzene was found to be 2.35 °C.The cryoscopic constant,K_f,for benzene is 5.12 °C kg/mol.Calculate the mole weight of the unknown.

A) 103 g/mol
B) 76.9 g/mol
C) 44.0 g/mol
D) 28.9 g/mol
E) 17.4 g/mol