posted by paul .
A solution which contains 40.3 g of an unknown molecular compound in 360 g of water freezes at -5.07°C.
What is the molar mass of the unknown?
delta T = Kf*m
Substitute and solve for molality.
molality = mols/kg solvent.
Substitute and solve for mols.
mols = grams/molar mass. You know grams and mols, solve for molar mass.