A student investigates different types of chemical reactions by adding dilute sulfuric acid, H2SO4(aq)\text{H}_2\text{SO}_4\text{(aq)}H2SO4(aq), to four separate solid reagents in test tubes.
Which of the following correctly describes both the classification of the reaction and the primary observations made?
With solid copper(II) oxide (CuO\text{CuO}CuO), the reaction is classified as a redox reaction, producing a blue solution and releasing oxygen gas.
With solid sodium hydroxide (NaOH\text{NaOH}NaOH), the reaction is classified as a precipitation reaction, producing a white precipitate of sodium sulfate.
With solid magnesium metal (Mg\text{Mg}Mg), the reaction is classified as a thermal decomposition, producing a colourless solution and releasing sulfur dioxide gas.
With solid copper(II) carbonate (CuCO3\text{CuCO}_3CuCO3), the reaction is classified as an acid-carbonate reaction, producing effervescence of an odourless gas and a blue solution.
55 exam-style questions on OCR GCSE Chemistry Types of chemical reactions. Each one has a worked solution and a mark scheme showing where the marks go.