A student adds dilute hydrochloric acid, a little at a time, to sodium hydroxide solution of pH 13. The student keeps adding acid until 50 cm3 of acid has been added. This is more than enough acid to neutralise the sodium hydroxide.
Which statement describes how the pH of the mixture changes?
it decreases from 13 to 7 and then stays at 7
it increases from 1 to 7 and then stays at 7
it increases from 1 to 13
it decreases from 13 to below 7
88 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.