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Question
Which of the following is amphoteric oxide?
\[\ce{Mn2O7, CrO3, Cr2O3, CrO, V2O5, V2O4}\]
Options
\[\ce{V2O5, Cr2O}\]
\[\ce{Mn2O7, CrO3}\]
\[\ce{CrO, V2O5}\]
\[\ce{V2O5, V2O4}\]
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Solution
\[\ce{V2O5, Cr2O}\]
Explanation:
\[\ce{V2O5}\] and \[\ce{Cr2O3}\] are amphoteric oxides because both react with alkalies as well as acids.
Remember: In lower oxides, the basic character is predominant while in higher oxides, the acidic character is predominant.
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