Question 1

This question is about displacement reactions. Iron is extracted from iron oxide by a displacement reaction with carbon. Balance the equation for the reaction:

Fe₂O₃ + 3C → __ Fe + __ CO

Accepted Answer

To balance a chemical equation, you must have the same number of atoms of each element on both the reactant (left) side and the product (right) side.
1. **Fe (Iron):** There are 2 Fe atoms on the left (in Fe₂O₃). So, you need 2 Fe atoms on the right. Place a 2 in front of Fe.
2. **O (Oxygen):** There are 3 O atoms on the left (in Fe₂O₃). You need 3 O atoms on the right. Placing a 3 in front of CO gives you 3 O atoms (and 3 C atoms).
3. **C (Carbon):** The equation already has 3C on the left. Placing a 3 in front of CO on the right gives 3 C atoms. The carbons are now balanced.
4. Check all elements are balanced.

Question 2

What mistakes do candidates make on this AQA GCSE question?

Accepted Answer

✗ Not having the same number of atoms of each element on both sides.
✗ Changing the small subscript numbers in the formulas.

This question is about displacement reactions. Iron is extracted from iron oxide by a displacement reaction with carbon. Balance the equation for the reaction:\n\nFe₂O₃ + 3C → Fe + CO

How to approach this question

Full Answer

Common mistakes

Practice the full AQA GCSE Chemistry Foundation Tier Paper 1

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