write the chemical equation of the reaction in which the following changes have taken place with an example of each : a) change in colour
(i) Change in colour: Reaction between lead nitrate solution and potassium iodide solution. In this reaction, colour changes from colourless to yellow.
(ii)Change in temperature: Action of dilute sulphuric acid on zinc. (iii) Formation of precipitate: Action of barium chloride on sodium sulphate.
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If you take some Copper Sulphate Solution and some Iron. Pour some iron in the solution and the Copper Sulphate solution will become Ferrous Sulphate solution, surely it is a Displacement Reaction but colour also changes because Copper Sulphate is bluish in colour while Ferrous Sulphate is greenish in colour.