A student measures the temperature change when zinc powder is added to copper sulfate solution.
They do the reaction in a polystyrene cup with a lid, not in a glass beaker.
Why does the student use a polystyrene cup with a lid?
To reduce energy transfer between the mixture and the surroundings
To make the zinc react with the copper sulfate more quickly
To stop the copper sulfate solution reacting with the container
To make sure that the reaction between them is exothermic
51 exam-style questions on OCR GCSE Chemistry 3.2 Energetics, covering 3.2.1 Exothermic and endothermic reactions and reaction profiles and 3.2.2 Calculating energy change from bond energies. Each one has a worked solution and a mark scheme showing where the marks go.