Twenty tablets (labelled 300 mg aspirin per tablet) had a total mass of 6.9117 g. The tablets were powdered and 0.5423 g of powder was added to 30.0 mL 0.494 M sodium hydroxide solution and the mixture boiled gently for 10 minutes. The excess alkali in the cooled solution was titrated with 0.475 M hydrochloric acid solution and 20.25 mL required for neutralization. Given that

You have been provided with a 2.08 x 10-2 L  sample of lithium hydroxide (LiOH) of unknown concentration. You perform a titration with 2.19 M nitric acid (HNO3), and find that 24.6 mL are required to reach the equivalence point (as determined using a coloured indicator). What is the concentration of the lithium hydroxide solution in mol L-1?

A student prepares a dilute solution of sodium hydroxide, NaOH (aq), starting with 6 M sodium hydroxide. She then titrates a 1.372 g sample of KHP with the dilute sodium hydroxide solution, NaOH (aq), to a phenolphthalein end point.   A.) If the titration required 21.84 mL of sodium hydroxide, NaOH (aq), calculate the molar concentration of the sodium hydroxide solution, NaOH (aq). (Remember that KHP is potassium hydrogen phthalate, KHC8H4O4, NOT potassium hydrogen phosphorus!)   B.) The student uses the same sodium hydroxide to titrate 10.00 mL of vinegar to a phenolphthalein end point. If the titration required 27.48 mL of sodium hydroxide, NaOH (aq), calculate the molar concentration of acetic acid, HC2H3O2 (aq), in the vinegar.   C.) Calculate the mass percent of acetic acid, HC2H3O2 (aq), in the vinegar using the molar concentration for acetic acid, HC2H3O2 (aq), determined in part b and assuming the density of the solution is 1.01 g/mL.

Normal calcium levels in the blood should be between 9.0 and 10.5 mg/dL. Calcium levels in the blood can be determined by adding oxalate ion to precipitate calcium oxalate, CaC2O4, followed by dissolving the precipitate in aqueous acid and titrating the resulting oxalic acid (H2C2O4) with KMnO4. 5 H2C2O4 (aq) + 2 MnO4–(aq) + 6 H+(aq) yields 10 CO2 (g) + 2 Mn2+(aq) + 8 H2O(l) What is the concentration of Ca2+ (mg/dL) in a 10.0 mL sample of blood if 10.54 mL of 9.88 x 10–4 M KMnO4 solution is needed for the titration.