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Question
The chemical reaction between two substances is characterised by a change in colour from orange to green. These two substances are most likely to be:
(a) potassium dichromate solution and sulphur dioxide
(b) potassium permanganate solution and sulphur dioxide
(c) potassium permanganate solution and lemon juice
(d) potassium dichromate solution and carbon dioxide.
Solution
(a) potassium dichromate solution and sulphur dioxide
Reaction between these two are characterised by change in colour. The orange colour of acidified potassium dichromate changes to green on passing sulphur dioxide.
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