An analytical chemist performs a titration to determine the concentration of a potassium hydroxide solution. They pipette 25.0 cm3 of the potassium hydroxide solution into a conical flask and add a few drops of phenolphthalein indicator. Dilute nitric acid is then added slowly from a burette until the reaction mixture just reaches its endpoint.
State the colour change of the phenolphthalein in the conical flask during this titration.
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.