A-LevelChemistryAnalytical techniquesMay/June 2022Paper 3 Q112 Marks
A bottle containing the acid salt sodium hydrogen sulfate, NaHSO4, has been contaminated. You will determine the percentage purity by mass of the sodium hydrogen sulfate by titrating a solution of the acid salt against a known concentration of sodium hydroxide. NaHSO4(aq) + NaOH(aq) → Na2SO4(aq) + H₂O(I) The impurity in the sodium hydrogen sulfate does not react with aqueous sodium hydroxide under the conditions of the titration. FB 1 is 0.100 mol dm-³ sodium hydroxide, NaOH. FB 2 is 12.53 gdm⁻³ impure sodium hydrogen sulfate. FB 3 is thymol blue indicator.
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