Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Reactions of metals with dilute acids
19 practice questions
Practice questions
1–3 of 3 · Hard
Question 1
2 marks · Hard
Answer and see the solution →A student places strips of magnesium and iron into separate test tubes containing excess dilute hydrochloric acid at room temperature. Only one test tube becomes noticeably warm and gives off gas rapidly.
State which metal is more reactive and explain your reasoning using the observations.
Question 2
5 marks · Hard
Answer and see the solution →A student investigates how sodium, magnesium, zinc, and silver react with dilute hydrochloric acid. She records her results in the table below:
Experimental results for reactions with dilute hydrochloric acid. Metal Observation Sodium Rapid fizzing, heat produced, gas collected, test tube very hot. Magnesium Vigorous fizzing, solution gets warm, gas collected. Zinc Steady fizzing, slight warmth, some gas collected. Silver No visible change. (a)[1 mark]Rank the four metals in order of reactivity with dilute hydrochloric acid, starting with the most reactive.
(b)[2 marks]Explain how the student’s observations support the order of reactivity you have given. Refer to at least two different metals in your explanation.
(c)[2 marks]State one reason why it is important to use the same number of moles of each metal when comparing their reactivity in this experiment.
Question 3
2 marks · Hard
Answer and see the solution →A student reacts equal moles of aluminium and iron separately with excess dilute hydrochloric acid at room temperature. The aluminium sample shows little to no fizzing at first but then reacts quickly when warmed. The iron sample reacts slowly, producing gentle fizzing throughout.
Use the observations to explain which metal is more reactive with dilute hydrochloric acid, and give a reason for aluminium’s unusual reaction pattern.