Aspirin is a monoprotic acid called acetylsalicylic acid. Its formula is HC9H7O4. A certain pain reliever was analyzed for aspirin by dissolving 0.311 g of it in water and titrating it with 0.0398 M KOH solution. The titration required 22.32 mL of base. What is the percentage by weight of aspirin in the drug?

1 answer

mols KOH = M x L = ?
mols aspirin = the same since both are monoprotic
g aspirin = mols x molar mass
%aspirin = (g aspirin/mass sample)*100 = ?