Question

Noble metals are dissolved in :

• A. conc. HNO${}_3$
• B. conc. HCl
• C. conc H${}_2$SO${}_4$
• D. aqua regia

Answer 1

The correct option is D aqua regia

A mixture of three parts of concentrated $HCl$ and one part of concentrated $HN{O}_3$ is known as aqua regia.

Aqua regia is a strong oxidizing agent. Aqua regia dissolves metals by first oxidizing them. Noble metals which are not prone to oxidation using other acids are oxidized easily by the action of aqua regia.

Hence, option $\text{D}$ is correct.