Molality
posted by Kyle .
An aqueous solution contains 8.7% NaCl by mass.
1. Calculate the molality of the solution.
2. Calculate the mole fraction of the solution.

assume 100 grams of the solution.
you have 8.7 g of NaCl, figure the moles
You have 91.3 g of water, figure the moles
calculate the mole fraction.
molality=molesNaCl/kgsolvent
and you have .1 kg solvent. 
1.49 m