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प्रश्न
What is meant by 22 carat gold? Name the metals which are usually alloyed with gold to make it harder.
उत्तर
An alloy of gold with copper or silver (Cu and Ag are mixed with gold to make it harder) is called 22 carat gold. The value refers to 22 parts of pure gold alloyed with two parts of either silver or copper. 22 carat gold is used for making jewellery.
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