Q5 of 59 Page 99

You have just won a medal made of 22-carat gold. Have you just procured a pure substance or impure substance?

It is an impure substance since the purity of gold is measured in terms of carat. 24 carat is the pure form of gold so 22 carat gold = (22/24) ×100 = is 91.66 % pure only. It is actually alloy of gold, silver and nickel.


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