How does aqua regia dissolves Gold and Platinum?

 

Asked by kartikmangaliya22.10spicertl | 27th May, 2020, 09:55: PM

Expert Answer:

Nitric acid (1 part by volume) mixed with conc. hydrochloric acid (3 parts by volume) produces a mixture called aqua regia.
 
HNO3 + 3HCl → NOCl + 2H2O + 2[Cl]
 
Aqua regia contains nascent chlorine and reacts with noble metals such as gold and platinum to produce chlorides.
 
Pt + 4[Cl] → PtCl4
Au +3[Cl] → AuCl3

Answered by Ramandeep | 27th May, 2020, 10:01: PM