Question
What is the mole fraction and mass percent of NaCl when the molality is 1.71m?
Answers
DrBob222
1.71m means 1.71 mols NaCl/kg solvent.
1 mol = 58.5 grams so 1.71 mol = about 100 grams; therefore, this is 100 g NaCl/(1.1 kg).
% w/w = (g solute/g solvent)*100 = about (100/1100)*100 = % w/w.
XNaCl = mols NaCl/total mols (you know mols NaCl from above; calculate mols H2O from the kg H2O in molality.)
1 mol = 58.5 grams so 1.71 mol = about 100 grams; therefore, this is 100 g NaCl/(1.1 kg).
% w/w = (g solute/g solvent)*100 = about (100/1100)*100 = % w/w.
XNaCl = mols NaCl/total mols (you know mols NaCl from above; calculate mols H2O from the kg H2O in molality.)