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प्रश्न
Give reasons
Gold is mixed with copper and nickel.
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उत्तर
Pure gold is a very soft metal. It cannot be moulded into ornaments so it is mixed with copper and nickel so that it becomes harder and bit cheaper also.
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संबंधित प्रश्न
Saloni took a piece of burning charcoal and collected the gas evolved in a test tube.
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