A certain headache relief tablet is composed of monoprotic acetylsalicylic acid(C9H8O4(s)) and an inert filler. A 4.00 g tablet was crushed and dissolved to make 40.0 mL of solution. The solution was then titrated with 0.900 mol/L NaOH(aq). The volume of NaOH(aq) needed to neutralize the dissolved tablet was 20.1 mL. The experimental value for the mass of C9H8O4(s) present in the tablet

was ___?

2 answers

moles NaOH = M x L = ? moles NaOH
moles ASA = same since the reaction (you should write the equation) is 1 mole ASA to 1 mol NaOH.
moles ASA= grams ASA/molar mass ASA.
You have moles and molar mass, solve for grams ASA.
If you want percent, then
percent ASA = (g ASA/4.00)*100 = x
3.26