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An aqueous solution contains 2.0 % NaCl by mass.
(1) Calculate the molality (NOT molarity!) of the solution.
(2) Calculate the mole fraction of the solution.
I know how to solve both but the problem is missing one other compound/element.
I know that molality is moles per kg of the solvent but I don't know what the solvent is. Is it water? Then how many kg of water?
As for the mole fraction, I know that number of moles of NaCl divided by the total number of moles but where will I get that other mole? Is it water again? How many will I use?
exactly what does "aqueous" mean?
So how many grams and moles of water will I use? I know water is missing compound and for the molality calculation, how many will I use? 1 gram and then covert that to kg?
How many moles will I use? One mole?
Nevermind, I got it. It was simply 100g minus 2g of NaCl (mass of the solvent, water).