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JEE Main202622 January 2026Evening ShiftChemistryd and f Block ElementsActual

Among the following oxides of 3 d elements, the number of mixed oxides are _ _ _ _ 。 Ti ₂ O ₃, ~V ₂ O ₄, Cr ₂ O ₃, Mn ₃ O ₄, Fe ₃ O ₄, Fe ₂ O ₃, Co ₃ O ₄

Correct answer

3

Step-by-step solution

Mixed oxides contain the same element in two different oxidation states. Analyzing each oxide: Ti₂O₃ contains Ti(+3) only - simple oxide. V₂O₄ contains V(+4) only - simple oxide. Cr₂O₃ contains Cr(+3) only - simple oxide. Mn₃O₄ can be written as MnO·Mn₂O₃, containing both Mn(+2) and Mn(+3) - mixed oxide. Fe₃O₄ can be written as FeO·Fe₂O₃, containing both Fe(+2) and Fe(+3) - mixed oxide. Fe₂O₃ contains Fe(+3) only - simple oxide. Co₃O₄ can be written as CoO·Co₂O₃, containing both Co(+2) and Co(+3) - mixed oxide. The

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