Potassium nitrate is used in fertilisers. A student makes potassium nitrate by reacting potassium hydroxide solution with dilute nitric acid. The student uses a titration.
Write the balanced equation for this reaction. Include state symbols.
Explain why potassium nitrate must be made by titration, and not by adding an excess of one reactant and filtering.
The student finds the volume of acid needed to neutralise 25.0 cm3\mathrm{cm^{3}}cm3 of potassium hydroxide solution, using an indicator. Describe how the student then uses this result to obtain pure, dry crystals of potassium nitrate.
The potassium hydroxide solution has a concentration of 0.200 mol dm−3\mathrm{mol\,dm^{-3}}moldm−3.
Calculate the number of moles of potassium hydroxide in 25.0 cm3\mathrm{cm^{3}}cm3 of this solution.
Calculate the maximum mass of potassium nitrate that can be made from 25.0 cm3\mathrm{cm^{3}}cm3 of this solution. Relative formula mass: KNO3=101\mathrm{KNO_{3}} = 101KNO3=101
44 exam-style questions on Edexcel GCSE Chemistry 4.1 Acids, covering 4.1.1 Acids, alkalis and the pH scale, 4.1.2 Hydrogen ion concentration and pH, 4.1.3 Dilute and concentrated, weak and strong acids, 4.1.4 Bases, alkalis and the reactions of acids, 4.1.5 Chemical tests for hydrogen and carbon dioxide, 4.1.6 Neutralisation as a reaction of acids with bases, 4.1.7 Preparing soluble salts, and 4.1.8 Solubility rules and preparing insoluble salts. Each one has a worked solution and a mark scheme showing where the marks go.