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Questions
With the help of an appropriate example, justify that some of the chemical reactions are determined by Change in colour
Give chemical equation for the reaction involved in the above case.
Give one example of a chemical reaction characterised by change in colour.
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Solution
When sulphur dioxide gas is passed through acidified potassium dichromate solution, orange colour of potassium dichromate solution changes to green colour.
\[\ce{3SO2(g) + K2Cr2O7(aq) + H2SO4(aq)->K2SO4(aq) + Cr2(SO4)3(aq) + H2O(I)}\]
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