The University of Nottingham published a video showing gold dissolve into aqua regia (a mixture of nitric acid and hydrochloric acid). Aqua Regia is a mixture of two acids, hydrochloric acid and nitric acid. Now the exciting thing about Aqua Regia is that neither of the two acids by themselves can dissolve gold. Nitric acid doesn’t really react with gold very much at all, and HCl, hydrogen chloric acid can’t get a hold of the gold to get the reaction going. But if you can put gold into solution that contains both acids, then it can react, and in fact, can indeed dissolve gold – which is why Aqua Regia is also known as ‘royal water.”
So, if you are thinking of getting some gold jewelry for your mom for Mother’s Day this weekend, you can treat her royally, but stay away from the aqua regia.