Vegetable oil reacts with hydrogen at 150 ∘C150\,^\circ\mathrm{C}150∘C to make margarine. Powdered nickel is added to the mixture. At the end, the nickel is filtered off and used again.
Which substance is the catalyst in this reaction?
Hydrogen
Margarine
Nickel
Vegetable oil
56 exam-style questions on OCR GCSE Chemistry 5.2 Controlling reactions, covering 5.2.1 Measuring and interpreting rate of reaction, 5.2.2 Factors affecting rate and collision theory, and 5.2.3 Catalysts, activation energy and enzymes. Each one has a worked solution and a mark scheme showing where the marks go.