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Question
Give an example and suggest a reason for the following feature of the transition metal chemistry:
The highest oxidation state is exhibited in oxoanions of a metal.
Solution
Metal oxoanions show higher oxidation states, for example, in \[\ce{Cr2O^{2-}_7}\] the oxidation state of Cr is +6, while in \[\ce{MnO^-_4}\] the oxidation state of Mn is +7. The reason for the combination of metal with oxygen is that oxygen is a highly electronegative and oxidizing element.
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