Consider one mole of the oxide, then
Moles of M = 0.98; Moles of O^{2- }= 1
Let 'x' moles of M are in +3 oxidation state, then Moles of M2+ = 0.98-x
On doing charge balancing we get
(0.98 - x)2 + 3x = 2
Or 1.96 - 2x + 3x - 2 = 0
Or x = 0.04
∴
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 the metal which exists as M3+ would be:
Held on 7 Apr 2013 · Verified 6 Jul 2026.
6.05\text{%}
5.08\text{%}
7.01\text{%}
4.08\text{%}
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