posted by Matt .
How many grams of HCl need to be dissolved in 0.5L of water to prepare a solution of pH 1.5?
Does anybody know how to work this out?
pH = -log(H^+)
1.5 = -log(H^+) and
(H^+) = about 0.032M but you do it more accurately.
How many mols do you want? That's M x L = 0.032 x 0.5L = about 0.016 mols.
mols = grams/molar mass. You know molar mass and mols, solve for grams.