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Question
When KOH solution is added to potassium dichromate solution the colour of solution
changes to yellow, because _______
(A) chromate ion changes to dichromate ion
(B) dichromate ion changes to chromate ion
(C) oxidation number of chromium changes from + 6 to + 4
(D) oxidation number of chromium changes from + 4 to +6
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Solution
dichromate ion changes to chromate ion.
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