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प्रश्न
lt was Paheli’s birthday. Her grandmother gave her two gifts made of metals, one old dull silver spoon and a pair of lustrous gold earrings. She was surprised to see the difference in the appearance of the two metals. Can you explain the reason for this difference?
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उत्तर
Gold is a noble metal it does not react with the gases present in the atmosphere. Silver reacts with some gases like hydrogen sulphide and loses its shine in moist air.
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