The four metals and hydrogen are placed in descending order of reactivity as follows: potassium, aluminium, zinc, hydrogen, copper. Which statement about these elements is correct?
- AAluminium is formed when aluminium oxide is heated with hydrogen.
- BCopper displaces zinc from zinc sulfate solution.
- CCopper is formed when copper(II) oxide is heated with hydrogen.
- DWhen added to water, aluminium forms positive ions more readily than potassium.