posted by Anonymous on .
A solutionof 2.50g of a compound having the empirical formula C7H6O2 in 25.0g of benzene is observed to freeze at 4.3 degree C.Calculate the molar mass of the solute and its Molecular formula
Look up normal freezing point benzene.
Look up freezing point constant for benzene (Kf = ?).
delta T = Kf*molality
Solve for molality.
molality = moles/kg solvent
Solve for moles
moles = grams/molar mass
Solve for molar mass.
Find the mass of the empirical formula.
(molar mass/empirical mass) = ?? and round to the nearest whole number and call that number n. The molecular formula is (empirical formula)n.