This question is about writing equations for reactions in solution.
Limewater is calcium hydroxide solution. It contains calcium ions, Ca²⁺, and hydroxide ions, OH⁻.
Write the formula of calcium hydroxide.
Carbon dioxide gas reacts with limewater. Calcium carbonate and water are made.
Calcium carbonate is insoluble in water.
Write the balanced symbol equation for this reaction. Include state symbols.
Aluminium sulfate is used in water treatment. It contains aluminium ions, Al³⁺, and sulfate ions, SO₄²⁻.
Write the formula of aluminium sulfate.
A student mixes silver nitrate solution with sodium chloride solution.
A white precipitate of silver chloride forms. Sodium nitrate stays dissolved in the solution.
Write the balanced ionic equation for the formation of the precipitate. Include state symbols.
Explain why sodium ions and nitrate ions are not included in the ionic equation.
55 exam-style questions on OCR GCSE Chemistry 3.1 Introducing chemical reactions, covering 3.1.1 Writing formulae and balanced chemical equations, 3.1.2 Formulae of compounds from ions, and state symbols, 3.1.3 Conservation of mass and observed changes in mass, 3.1.4 Half equations and balanced ionic equations, 3.1.5 The mole and the Avogadro constant, and 3.1.6 Stoichiometry, limiting reactants and reacting masses. Each one has a worked solution and a mark scheme showing where the marks go.