Acid test (gold) Wikipedia
An acid test is any qualitative chemical or metallurgical assay which uses acid; most commonly, . If the mark remains, it is tested by applying aqua regia (nitric acid and hydrochloric acid). If the mark is removed, then this test dissolves the gold,.
Aqua regia Wikipedia
Aqua regia is a mixture of nitric acid and hydrochloric acid, optimally in a molar ratio of 1:3. Aqua regia is a yellow orange (sometimes red) fuming liquid, so named by alchemists because it can dissolve the noble metals gold and platinum, though not all metals. Contents. 1 Applications; 2 Chemistry .. As with gold, the oxidation reaction can be written with either nitric oxide or.Get Price