Question
When three parts of cone. $$HCl$$ and one part of cone. $$HN{O_3}$$ is mixed, a compound $$'X'$$ is formed. The correct option related to $$'X'$$ is
A.
$$'X'$$ is known as aqua-regia
B.
$$'X'$$ is used for dissolving gold
C.
$$'X'$$ is used for decomposition of salts of weaker acids
D.
both (A) and (B)
Answer :
both (A) and (B)
Solution :
$$3HC{l_{\left( {conc.} \right)}} + HN{O_{3\left( {conc.} \right)}}$$ \[\to \underset{\begin{smallmatrix}
\left( X \right) \\
\text{Aqua regia}
\end{smallmatrix}}{\mathop{NH{{O}_{3}}\cdot 3HCl}}\,\]
Aqua regia is used for dissolving noble metals like gold, platinum. $$HCl$$ decomposes salts of weaker acids e.g., carbonates, hydrogen carbonates, sulphites, etc.