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Question
Give reason for the following:
Blue solution of copper sulphate changes to green when a piece of iron is added to this solution.
Solution
This is because the blue colour of the copper sulphate solution fades and eventually turns into light green due to the formation of ferrous sulphate.
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| 7.`2H_2O` `→` `2H_2``↑`+`O_2` | e. combination or synthesis reaction |
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