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Ion ratio in magnetite
The most common oxides of iron are Fe₂O₃ and Fe₃O₄.
What is the ratio of the numbers of ions in Fe₃O₄? Tick one box.
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Marking points
- 1 Selects 1 Fe²⁺ : 2 Fe³⁺ : 4 O²⁻.
Why this answer loses marks
I counted only the atoms shown in the formula.
Atom counts are not enough; balance total positive and negative charge across the mixed iron ions.