i answered ALL the questions but THIS ONE. agggh help?

0 ⤊

i answered ALL the questions but THIS ONE. agggh help?

Solvent: para-dichlorobenzene
Freezing point of pure solvent: 53.02 C
Mass of unknown substance: 2.04 g
Freezing point depression constant: 7.1 C/m
Mass of para-dichlorobenzene: 24.80 g
Freeezing point of solution: 50.78 C

Calculate molar mass of solute??

I got something in the 200s...

2007-10-28 12:10:23 · 1 answers · asked by Bao Pham 3 in Science & Mathematics ➔ Chemistry

1 answers

Freezing point depression: 50.78C - 53.02C = -2.24C
Molality of the solute: 2.24C/(7.1 C/m) = 0.315 m
Moles of solute in the solution: 0.315 *(24.80/1000) = 0.00782 mole
The molar mass of solute: 2.04g /(0.00782 mole) = 261 g/mol

2007-10-31 13:30:47 · answer #1 · answered by Hahaha 7 · 0⤊ 0⤋