Question 3(b)(iv)
[Maximum number: 1]
Iron is manufactured in a blast furnace.
The source of iron in the blast furnace is . is found in iron ore.
Explain how the change of oxidation number shows that iron has been reduced.
CAIE IGCSE Chemistry Electron Gain and Oxidation Number Decrease
Practise identifying reduction from electron gain or an oxidation-number decrease and selecting or completing reduction half-equations accurately.
How this is tested
- define reduction as gain of electrons or a decrease in oxidation number
- identify the reduced species by finding the electron acceptor in an ionic equation
- write a balanced reduction half-equation with the gained electrons on the left