Question

A mixture of three parts of Conc. $\mathrm{HCl}$ and one part of Conc. Nitric Acid.

Answer 1

• A mixture of three parts of Conc. $HCl$ and one part of Conc. Nitric Acid is Aqua regia $(HN{O}_3+3HCl)$.
• When any $2$ very strong acids get combined and they react together they form a highly acidic solution.
• Aqua regia has this tendency of dissolving the noble metals and that is acidic, oxiditative and corrosive mixture, though $HCl$ and Nitric Acid can’t do this alone.