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.
Gold is unaffected by air, water, alkalis and all acids except aqua regia (a mixture of hydrochloric acid and nitric acid) which can dissolve gold.
Complete step by step answer
We know that most powerful acids like hydrochloric acid and nitric acid alone are not able to dissolve gold. This is because gold being one of the least reactive metals is not able to replace the hydrogen from the given acids as it is also less reactive than the hydrogen.
Aqua regia is used to dissolve gold. Neither nitric acid or hydrochloric acid can do this alone. Nitric acid will act as the oxidizer and is used to form gold ions (Au3+).
The most useful and important vehicle for dissolving gold is aqua regia, (royal water), composed of two parts of hydrochloric (muriatic) acid, and one part of nitric (aquafortis).
The only way gold could truly be destroyed is through nuclear reactions. However, there does exist a way to dissolve gold using “Aqua Regia,” which is a mix of hydrochloric and nitric acids.
Metallic gold dissolves in hot strong sulphuric acid, especially if a little nitric acid is added (the precipitated metal dissolving most readily), forming a yellow liquid, which, when diluted with water, deposits the metal as a violet or brown powder.
One study showed that when a 14K white gold ring was placed in common household bleach for 36 hours, the ring completely disintegrated! Small amounts of chlorine exist in tap water, too.
[4], showing that gold is not oxidized at all when water is oxidized to elemental oxygen (the higher of the two red lines) and that even hydrogen peroxide with its potential at half a volt higher is only on the borderline of beginning to oxidize gold.
Hydrogen peroxide is suitable to clean gold (yellow gold, white gold, rose gold), platinum as well as silver jewelry. Hydrogen peroxide will act as a boosting agent to get rid of the muck and grime embedded into your jewelry. For the most effective formula, combine mild detergent with water.
The researchers have taken that next step and shown that highly concentrated solutions of aluminum chloride and aluminum nitrate can also readily dissolve gold as well as the platinum group noble metals.
No, lower karat gold alloys will dissolve more quickly than higher karat alloys because they contain more copper or silver, which dissolve in nitric acid, while gold does not.
Cyanide easily combines with many metals—making it useful in separating metals like gold from their ore.
Gold is one of the noblest—that is, least chemically reactive—of the transition elements. It is not attacked by oxygen or sulfur, although it will react readily with halogens or with solutions containing or generating chlorine, such as aqua regia.
The strongest of them all
That title falls to fluoroantimonic acid – a superacid mixture of antimony pentafluoride and hydrofluoric acid.
The purer the gold, the stronger the acid required to dissolve it. Measured strengths of nitric acid are used to test for 14k and lower. Aqua regia, a mixture of one part nitric acid and three parts hydrochloric acid, is used to test higher karat purity through the process of comparison and elimination.
Vinegar is incredibly corrosive. So, if your gold jewelry is made of a different metal or alloy, the vinegar will cause it to tarnish. Gold is a non-reactive metal, so it will not react to vinegar.
As is well known, aqua regia (a mixture of three parts hydrochloric acid to one part nitric acid) can dissolve gold.
If your gold piece turns black or green when the vinegar is on it, or if it starts to smoke or fizzle at all when the vinegar touches it, it is most likely not real gold. If your gold piece does not change colors and does not fizzle or react to the vinegar in any way, it is probably real.
Gold will not be affected by acetone. It is not harmful to consume gold because it is tasteless. Acetone, in addition to being an organic solvent, is a widely recognized solvent.
It is possible to dissolve gold in ammonia solution at room temperature according to the thermodynamics of the Au-NH3-H2O system. But it has been reported in the literature that the kinetics of gold dissolution is very poor at low temperatures.
Chlorine in swimming pools, hot tubs, and even cleaning supplies, will attack the other metals that are alloyed with your gold. It literally leaches out the nickel and zinc and silver, leaving microscopic bubbles inside your jewelry. And when this happens, your karat gold jewelry will become brittle and weak.
Aqua Regia Solution Preparation:
Slowly add the nitric acid to the hydrochloric acid (NEVER the other way around) to form a 3:1 ratio solution of three parts hydrochloric acid, and one part nitric acid. Stirring with a stir bar and plate is recommended.
What to do: Hold the magnet up to the gold. If it's real gold it will not stick to the magnet. (Fun fact: Real gold is not magnetic.) Fake gold, on the other hand, will stick to the magnet.
Gold is an inert metal and is therefore not degraded by the acid in our stomachs. It will travel the length of the intestinal system unchanged, passing out in your poo.