Question
What is the mole fraction of solute and the molal concentration for an aqueous solution that is 19.0% NaOH by mass?
Answers
19% w/w NaOH means 19 g NaOH/100 g soln or 19g NaOH/(19g NaOH + 81 g H2O)
moles NaOH = grams/molar mass
moles H2O = grams/molar mass
XNaOH = moles NaOH/total mols.
m = moles NaOH/kg solvent.
moles NaOH from above. kg solvent from above.
moles NaOH = grams/molar mass
moles H2O = grams/molar mass
XNaOH = moles NaOH/total mols.
m = moles NaOH/kg solvent.
moles NaOH from above. kg solvent from above.
0.25