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प्रश्न
2 mL each of concentrated HCl, HNO3 and a mixture of concentrated HCl and concentrated HNO3 in the ratio of 3 : 1 were taken in test tubes labelled as A, B and C. A small piece of metal was put in each test tube. No change occurred in test tubes A and B but the metal got dissolved in test tube C respectively. The metal could be
पर्याय
Al
Au
Cu
Pt
उत्तर
Au
Explanation -
A mixture of concentrated HCl and concentrated HNO3 in the 3 : 1 molar ratio is called aqua regia. It is a yellow-orange fuming liquid that can dissolve gold.
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