Question

g Calculate the molar mass of naphthalene, the organic compound in mothballs, if a solution is prepared by dissolving 5.00 g of naphthalene in exactly 100 g of benzene has a freezing point 2.0 oC below that of pure benzene (Kf of benzene is 5.12 oC/m).

Answer 1

Step-by-step explanation:

no of moles of solute dissolved = 2 / 5.12

= .3906 moles

amount of solute = .100 kg of benzene x .3906 = .03906 moles

molecular weight of naphthalene = 5 / .03906

= 128 g /mole