The freezing point of a sample of naphthalene was found to be 80.6 oC. When 0.512 g of a substance is dissolved in 7.3 g naphthalene, the solution has a freezing point of 75.2oC. What is the molar mass of the solute. The Kf of naphthalene = 6.80oC/m.

PS. If you can, please include a complete solution. TIA