A technician is selecting a substance to neutralise acidic waste water. Two substances, P and Q, are tested.
| Substance | Result when added to dilute acid | Result when added to water |
|---|---|---|
| P | A salt and water form | The substance does not dissolve |
| Q | A salt and water form | The substance dissolves and the solution contains hydroxide ions |
The technician claims, “Every base is an alkali.”
Evaluate the technician's claim using all the test results.
112 exam-style questions on OCR GCSE Chemistry 3.3 Types of chemical reactions, covering 3.3.1 Oxidation and reduction in terms of oxygen, 3.3.2 Acids, alkalis and neutralisation, 3.3.3 The pH scale and measuring pH, 3.3.4 Oxidation and reduction in terms of electrons, 3.3.5 Dilute and concentrated, weak and strong acids, and 3.3.6 Hydrogen ion concentration and pH. Each one has a worked solution and a mark scheme showing where the marks go.