Which statement about a catalyst on a reaction profile is correct?
It lowers the energy of the products, so more energy is released
It lowers the peak; reactant and product levels are unchanged
It raises the energy of the reactants, so the barrier is smaller
It lowers the peak and also lowers the product energy level
53 exam-style questions on Edexcel GCSE Chemistry 8.2 Heat energy changes in chemical reactions, covering 8.2.1 Exothermic and endothermic changes, 8.2.2 Bond breaking, bond making and overall energy change, 8.2.3 Calculating energy change from bond energies, and 8.2.4 Activation energy and reaction profiles. Each one has a worked solution and a mark scheme showing where the marks go.