How many grams of naphthalene, C10H8, would you add to 49.5 g of benzene, C6H6 (l), to produce a solution that has the same freezing point as pure water? (Use the data from the table as needed.)
Molal Freezing Point Depression and Molal Boiling Point Elevation Constants:
Solvent Normal Freezing K(fr) Normal Boiling K(br)
Point,C C m^-1 Point, C C m^-1
Acetic acid 16.63 3.90 117.90 3.07
Benzene 5.53 5.12 80.10 2.53
Cyclohexane 6.55 20.0 80.74 2.79
Nitrobenzene 5.8 8.1 210.8 5.24
Water 0.00 1.86 100.00 0.512
In the dilute ideal solutions, the extent of freezing-point depression is directly proportional to the molal concentration of the solution
deltaTf = Kf · m
where deltaTf = Tf(pure solvent benzene) - Tf(solution as water) = 5.53 - 0 = ...
It determines the freezing point of naphthalene and benzene mixture. The solution is detailed and has a rating of '5/5'.