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Question
Which of the following will not act as oxidising agents?
(i) \[\ce{CrO3}\]
(ii) \[\ce{MoO3}\]
(iii) \[\ce{WO3}\]
(iv) \[\ce{CrO^{2-}4}\]
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Solution
(ii)\[\ce{MoO3}\]
(iii) \[\ce{WO3}\]
Explanation:
A compound act as oxidising agent when it’s central atom is reduced to its lower oxidation state. This occurs only when the lower oxidation state of metal is more stable than the higher oxidation states.
In metal \[\ce{WO3}\] and \[\ce{CrO4^{2-}}\], both W and Cr are stable in their higher oxidation state and won’t get reduced to their lower oxidation state. Therefore, will not act as oxidising agents.
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