A student carries out a titration by adding dilute nitric acid from a burette to a conical flask containing potassium hydroxide solution and a few drops of indicator.
Which of the following correctly describes the indicator and the colour change at the end point of this titration?
Phenolphthalein | Colourless to pink
Phenolphthalein | Pink to colourless
Methyl orange | Red to yellow
Methyl orange | Blue to red
276 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.