A 2.97 g sample of a molecular compound

is dissolved in 103 g of tetrachloromethane
(carbon tetrachloride). The normal boiling
point of the solution is 61.51�C, the normal
boiling point of CCl4 is 61.2�C. The boiling
point constant for CCl4 is 4.95 K · kg/mol.
What is the molar mass of the compound?

2 answers

delta T = Kb*molality
Solve for molality

m = moles/kg solvent
Solve for moles

moles = grams/molar mass
Solve for molar mass.
pv=nrt