Aqua Regia Dissolving Gold

Au + 3HCl + HNO3 → HAuCl4 + NO + 2H2O

概要

Aqua regia (3:1 mixture of HCl and HNO₃) dissolves gold, which is inert to either acid alone. Nitric acid oxidizes gold to Au³⁺ while hydrochloric acid provides chloride ions that stabilize the gold as [AuCl₄]⁻ complex. The synergy between the two acids makes aqua regia effective against noble metals.

参加者

役割 物質 係数 状態
反応物 Gold Au 1 (s)
反応物 Nitric Acid HNO₃ 1 (aq)
反応物 Hydrochloric Acid HCl 3 (aq)
生成物 Water H₂O 2 (l)

日常の例

During WWII, George de Hevesy dissolved the Nobel Prize gold medals of Max von Laue and James Franck in aqua regia to hide them from the Nazis.

産業上の重要性

王水は金の精錬、貴金属を溶解する分析化学、そして電子廃棄物からの貴金属回収に使用されています。

特性

タイプ
Redox
可逆的
いいえ
エネルギー
発熱性
ΔH
-150.0 kJ/mol

関連する反応

Iron(II) to Iron(III) Oxidation by Oxygen Bleaching with Sodium Hypochlorite Copper Reduction of Silver Ion Cerium(IV) Reduction by Iron(II) Chlorine Oxidation of Bromide Copper Oxidation by Nitric Acid Hypochlorite Oxidation of Hydrogen Peroxide Hydrogen Peroxide as Oxidizing Agent (Acidic) Zinc Reduction of Silver Ion Displacement of Hydrogen from Acid by Magnesium

Frequently Asked Questions

What is the equation for Aqua Regia Dissolving Gold?
The balanced equation is: Au + 3HCl + HNO₃ → HAuCl₄ + NO + 2H₂O.
What type of reaction is Aqua Regia Dissolving Gold?
Aqua Regia Dissolving Gold is a redox reaction.
Is Aqua Regia Dissolving Gold exothermic or endothermic?
Aqua Regia Dissolving Gold is exothermic (releases energy). The enthalpy change (ΔH) is -150.0 kJ/mol.