A student adds dilute hydrochloric acid to a solid sample of copper(II) carbonate in a test tube. A rapid effervescence is observed, a gas is evolved, and a blue-green solution is formed.
Which of the following describes the correct test and observation to identify the gas produced?
Hold a lighted splint near the mouth of the test tube; the gas burns with a characteristic 'squeaky pop'.
Insert a glowing splint into the test tube; the splint relights.
Bubble the gas through limewater; the liquid turns cloudy.
Hold damp blue litmus paper near the mouth of the test tube; the paper turns red and is then bleached white.
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.