A student investigates the reactivity of four different metals (magnesium, zinc, iron, and tin) by measuring the temperature increase when each metal is added to dilute hydrochloric acid.
In their initial trial, the student used a magnesium ribbon, zinc granules, iron filings, and a tin strip.
Explain how the student could improve the method to make a fairer comparison of the temperature change produced by the different metals.
110 exam-style questions on Edexcel GCSE Chemistry 5.1 Obtaining and using metals, covering 5.1.1 The reactivity series of metals, 5.1.2 Displacement reactions as redox reactions, 5.1.3 Extracting metals from ores by reduction, 5.1.4 Biological methods of metal extraction, 5.1.5 Resistance to oxidation and recycling metals, and 5.1.6 Life cycle assessment. Each one has a worked solution and a mark scheme showing where the marks go.