- Page 1Introduction - ReviewIntroduction to the importance of problem planning and relationships used to solve stoichiometry problems
- Page 2Solving stoichiometry problems - Review
- 15 marksPage 3Problem 1The concentration of a solution of sulfuric acid is determined by titration with 0.1050 mol L–1 NaOH. Titration of 20.00 mL of the sulfuric acid requires 35.21 mL of the NaOH solution to reach an endpoint detected using methyl orange as the indicator. The reaction occurring in the flask is given below. Calculate the concentration of the sulfuric acid in the solution.
H2SO4(aq) + 2NaOH(aq) → Na2SO4(aq) + 2H2O
- 15 marksPage 4Problem 2The concentration of Ca(OH)2 in a limewater solution is 0.0378 mol L–1. Calculate the volume of 0.0508 mol L–1 HCl required to titrate 25.00 mL of the limewater to a phenolphthalein endpoint.
Ca(OH)2(aq) + 2HCl(aq) → CaCl2(aq) + 2H2O
- 20 marksPage 5Problem 3Battery acid having a density of 1.239 g mL–1 is to be analysed for sulfuric acid content. 1.00 mL of battery acid is diluted to 250.0 mL. 10.00 mL of the solution is titrated by 16.22 mL of 0.01992 mol L–1 NaOH to a phenolphthalein end point. Calculate the mass percent of H2SO4 in the battery acid.
2NaOH(aq) + H2SO4(aq) → Na2SO4(aq) + 2H2O