A statue coated with chemical substance X on long exposure to polluted – InterviewSolution

InterviewSolution

1.	A statue coated with chemical substance X on long exposure to polluted atmosphere becomes black. This colour can be restored by treatment with H_2O_2. Identify element X and also the types of chemical changes involved.
Answer» Solution :(i) metal PRESENT in paints which GETS darkened (black) on long exposure to polluted AIR (ii) nature of `H_2O_2` (iii) CHANGE in the colour of the compound when washed with `H_2O_2`

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