A 3.314−g sample of a mixture of cyclohexane (C6H12) and naphthalene (C10H8) is dissolved in 45.40 g of benzene (C6H6). The freezing point of the solution is 2.00 ° C. Calculate the mass percent of the mixture.
The molar masses of cyclohexane and naphthalene are 84 g/mol and 128 g/mol respectively.
In 3.314−g sample, let x g of a mixture of cyclohexane (C6H12) is present. 3.314-x g of naphthalene will be present.
The number of moles of cyclohexane
The number of moles of naphthalene
Total number of moles
45.40 g of benzene corresponds to 0.04540 kg.
The molality of solution is the number of moles of solute present in 1 kg of benzene.
Molality
The freezing point of the solution is 2.00 ° C.
The freezing point of benzene is 5.50 ° C.
The depression in the freezing point
For benzene,
The depression in the freezing point
The mass percent of cyclohexane
%.
Hence, 37.9 % cyclohexane is present.
The mass percent of naphthalene
A 3.314−g sample of a mixture of cyclohexane (C6H12) and naphthalene (C10H8) is dissolved in 45.40...
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