A solution of concentrated NaOH is 16.4 M. If the density of the solution is 1.43 g/mL what is the percent by mass NaOH?

1 answer

% w/w = grams solute/100 g solution.
16.5M = 16.4 mols/L solution.
grams = mols x molar mass so 16.4 x 40 = ? grams NaOH/L solution and that divided by 10 = grams NaOH/100 mL of solution.
Then mass = volume x density. You know density and volume, that will give you the mass of 100 mL solution.
Then % w/w= (grams NaOH in that mass of solution)*100 = ?