Q49 · Practice questionComplex familiar5 marks
QUESTION 49 (5 marks)
In acidic solution, permanganate oxidises iron(II) to iron(III) and is reduced to manganese(II).
a) Write the two balanced half-equations. [3 marks]
b) Combine them into a balanced net ionic equation. [2 marks]
WORKED SOLUTION
5 marksPractice marking scheme
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Balance oxygen with water, hydrogen with H⁺ and charge with electrons. Multiply the iron half-equation by five and cancel the electrons.
- Balances Mn/O/H in the reduction half-equation. [1 marks]
- Includes five electrons on the correct side. [1 marks]
- Writes the iron oxidation half-equation. [1 marks]
- Matches electron numbers. [1 marks]
- Writes the complete balanced net ionic equation. [1 marks]
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