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Experimentally it was found that a metal oxide has formula M0.98O. Metal M is present as M2+ and M3+ in its oxide. Fraction of metal which exists as M3+ would be -

1. 6.05%
2. 5.08%
3. 7.01%
4. 4.08%

Correct answer: 4.08%

Solution

To find the fraction of metal M that exists as M3+, we can set up a balance of charges in the oxide formula M0.98O. Given that M is present as both M2+ and M3+, we can express the total amount of metal in terms of its oxidation states and solve for the fraction of M3+, leading to the conclusion that 4.08% of the metal is in the M3+ state.

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