A student puts dilute hydrochloric acid and a few drops of phenolphthalein indicator into a conical flask.
She adds sodium hydroxide solution from a burette until the end point is reached.
What is the colour change at the end point?
Colourless to pink
Pink to colourless
Red to yellow
Yellow to red
57 exam-style questions on OCR GCSE Chemistry 5.1 Monitoring chemical reactions, covering 5.1.1 The technique of titration, 5.1.2 Theoretical mass, percentage yield and atom economy, 5.1.3 Concentration of a solution in mol/dm3, 5.1.4 Concentration calculations and titration results, 5.1.5 Molar gas volume and volumes of gases in reactions, and 5.1.6 Choosing a reaction pathway. Each one has a worked solution and a mark scheme showing where the marks go.