Which of the following is used to dissolve gold?A. Hydrochloric AcidB. Sulphuric AcidC. Nitric AcidD. Aqua Regia (2024)

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Which of the following is used to dissolve gold?A. Hydrochloric AcidB. Sulphuric AcidC. Nitric AcidD. Aqua Regia? ›

Final answer: Aqua Regia is used to dissolve gold.

Aqua regia is used to dissolve noble metals such as Pt(Platinum) and Au(Gold).

Aqua regia is a chemical solution that is obtained by mixing three parts nitric acid and one part hydrochloric acid. It can dissolve gold, platinum, titanium, and other noble metals.

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 hydrochloric acid is then used to react with the gold ions to form tetrachloroaurate(III) anions.

In addition, since gold is not easily dissolved in a sulfuric acid solution, gold grade is improved in the solid residue.

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).

Aqua regia, Latin for 'royal water', is a highly corrosive mixture of acids, famously known for its ability to dissolve gold. It is created by combining nitric acid and hydrochloric acid, typically in a volumetric ratio of 1:3.

Gold metal will not dissolve in either concentrated nitric acid or concentrated hydrochloric acid. It will dissolve, however, in aqua regia, a mixture of two concentrated acids.

Complete answer:As we know that gold is a less reactive metal so it can only be dissolved in Aqua regia. Now Aqua regia is a yellow-orange or a red-orange fuming and a corrosive liquid which is made up of a mixture of hydrochloric acid $(HCl)$ and nitric acid $(HN{O_3})$ .

Aqua regia is a mixture of nitric acid and hydrochloric acid in the molar ratio 1:3. It can dissolve noble metals like gold and platinum.

What does aqua regia dissolve? ›

It is called aqua regia because it is one of the few acid mixtures that can dissolve the “noble” metals: gold (Au), platinum (Pt), and palladium (Pd).

It is commonly used to remove noble metals such as gold, platinum and palladium from substrates, particularly in microfabrications and microelectronics labs. Glassware may also be washed with aqua regia to remove organic compounds only in trace amounts.

Aqua-regia is reagent is able to dissolve gold and platinum.

Aqua regia is a mixture of hydrochloric acid and nitric acid in the ration 3:1. It is a very strong acid and can dissolve any metals including noble metals like gold and silver.

Final answer: Aqua Regia is used to dissolve gold.

The metals that come below hydrogen in the electrochemical series usually are very less reactive metals. That is why they cannot replace hydrogen and hence do not usually react with nitric acid, while the ones above hydrogen react with nitric acid very efficiently. This is the general concept.

Aqua regia is used for dissolving gold. Aqua regia is a mixture of concentrated nitric acid and concentrated hydrochloric acid in the ratio of c$1:3$.

Cyanidation (and thiosulfate)

The principal technology is the cyanide process, in which gold is leached from the ore by treatment with a solution of cyanide.

Aqua regia is a fuming liquid. Freshly prepared aqua regia is colorless, but it turns yellow, orange or red within seconds from the formation of nitrosyl chloride and nitrogen dioxide. It was named by alchemists because it can dissolve noble metals like gold and platinum, though not all metals.

For extracting gold from low-grade ores, heap leaching is practiced. The huge heaps described above are sprayed with a dilute solution of sodium cyanide, and this percolates down through the piled ore, dissolving the gold.