At a metal-recycling plant, metal fragments react with a solution in a sealed vessel that contains air above the solution. Each batch must use the same mass of metal and the same volume and concentration of solution.
Which change increases the rate of this reaction?
Let each batch react for a longer time.
Raise the temperature of the reaction mixture.
Increase the pressure of the air above the solution.
Press the metal fragments into one solid block.
122 exam-style questions on Edexcel GCSE Chemistry 8.1 Rates of reaction, covering 8.1.1 Measuring and interpreting rates of reaction, 8.1.2 Collision theory and the factors affecting rate, and 8.1.3 Catalysts and enzymes. Each one has a worked solution and a mark scheme showing where the marks go.