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phat2107
Feb17-10, 07:38 PM
1. The problem statement, all variables and given/known data
"A 1.60 g sample of a mixture of naphtalene, C10H8. and anthracene, c14H10 is dissolveed in 20.0g of benzene, C6H6. The freezing point of the solution is 2.81C. Pure Benzene freezes at 5.51C and has a Kf = 5.12C kg/mol. Determine the composition (mass percentage) of naphthalene-anthracene mixture?"

my question is are they asking us for the easy mass composition of the Nap. and ant. mixture over the total mass or are they asking me to find the actual mass % between nap and ant., as in how many grams out of the 1.6 is the mass of nap?

2. Relevant equations



3. The attempt at a solution
if the question is as easy as it seems:
1.6/21.6 = 7.4%

Borek
Feb18-10, 02:21 AM
No, they ask about % composition of the original mixture - how many percent of naphtalene, how many perecent of anthracene.

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