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One day Reeta went to a jeweller’s shop with her mother. Her mother gave old gold jewellery to the goldsmith to polish. Next day when they brought the jewelry back, they found that there was a slight loss in its weight. Can you suggest a reason for t...
Materials: Metals and Non-Metals
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13/04/2021 12:44 pm
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One day Reeta went to a jeweller’s shop with her mother. Her mother gave old gold jewellery to the goldsmith to polish. Next day when they brought the jewelry back, they found that there was a slight loss in its weight. Can you suggest a reason for the loss in weight?
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13/04/2021 12:45 pm
The gold jewellery is dipped into an acidic solution called aqua regia (a mixture of hydrochloric acid and nitric acid) for polishing. On dipping the gold jewellery in the acid solution, the outer layer of gold dissolves and the inner shiny layer appears. This causes a slight loss in its weight.
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