The composition of a sample of wustite is `Fe_(0.93)O_(1.00)` What percentage of iron is present in the form of `Fe(III)`?

Explanation

`Fe_(0.93)O_(1.0)` is non - stoichiometric and a mixture of `Fe^(2+) and Fe^(3+)` ions. Let x atoms of `Fe^(3+)` ions are present in the compound. This means that x ` Fe^(3+)` ions have been replaced by `Fe^(2+)` ions.
No of `Fe^(2+) ions = 0.93 - x`
For electrical neutrality,
Positive charge on the compound = Negative charge on the compound.
`2(0.93 - x) + 3x = 2`
` 1.86 + x = 2`
` x = 0.14`
`% "of " Fe^(3+)" ions present" = (0.14)/(0.93) xx 100 = 15.05 %`