Copper oxide is added to dilute sulfuric acid until the copper oxide is in excess.
Why is the copper oxide added in excess?
to make sure all of the acid reacts
to make sure all of the oxide reacts
to make the reaction happen more quickly
to make the salt crystals larger
40 exam-style questions on AQA GCSE Chemistry 4.2 Reactions of acids, covering 4.2.1a Reactions of acids with metals, 4.2.1b Redox in acid-metal reactions, 4.2.2 Neutralisation of acids and salt production, 4.2.3 Soluble salts, 4.2.4 The pH scale and neutralisation, 4.2.5a Titrations, 4.2.5b Calculating quantities in titrations, and 4.2.6 Strong and weak acids. Each one has a worked solution and a mark scheme showing where the marks go.