Question

Aqua-regia dissolves gold. Which is correct?
A. Aqua regia, or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution.
B. The mixture is formed by freshly mixing concentrated nitric acid and hydrochloric acid optimally in a volume ratio of $1:3$.
C. It can dissolve the noble metals gold and platinum
D. All of these

Answer 1

Hint: We know that both are acidic in nature, the compound hydrochloric acid and nitric acid. We take both the chemicals in a concentrated form to form aqua regia.

Complete step by step answer:
As we all know, the aqua regia is one of the mixtures of concentrated hydrochloric acid and concentrated nitric acid in the part of $3:1$. It is a yellow-orange fuming liquid, and it can also dissolve the noble metals like gold, platinum, silver while its dissolving property of non-metals is not so good.
The given statement A that is “Aqua regia or nitro-hydrochloric acid is a highly corrosive mixture of acids, a fuming yellow or red solution” is true.
The given statement B that is “The mixtures is formed by freshly mixing concentrated nitric acid and hydrochloric acid optimally in a volume ratio of $1:3$” is also true.
The given statement C that is “It can dissolve the noble metals gold and platinum” is also true.
Thus, all the given statements are correct and give the information of aqua regia.

So, the correct answer is “Option D”.

Note:
The application of aqua regia is written below.
1. It is used as a cleaning agent in the chemical laboratories.
2. It is used for preparing other chemical species like chloroauric acid.