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Question
Why is FeO (s) not formed in stoichiometric composition?
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Solution
In the crystals of FeO, some of the Fe2+ cations are replaced by Fe3+ ions. Three Fe2+ ions are replaced by two Fe3+ ions to make up for the loss of positive charge. Eventually there would be less amount of metal as compared to stoichiometric proportion.
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RELATED QUESTIONS
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Frenkel defect
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