Gold element silver (as electrum) and also naturally alloyed with copper and palladium. Less commonly, it occurs in minerals as gold compounds, often with tellurium (gold tellurides). Gold is resistant to most acids, though it does dissolve in aqua regia, a mixture of nitric acid and hydrochloric acid, which forms a soluble tetrachloroaurate anion. Gold is insoluble in nitric acid, which dissolves silver and base metals, a property that has long been used to refine gold and to confirm the presence of gold in metallic objects, giving rise to the term "acid test". Gold also dissolves in alkaline solutions of cyanide,
Trifluoroacetic acid causes severe skin burns and is toxic for aquatic organisms even at low concentrations. TFA's reaction with bases and metals, especially light metals, is strongly exothermic. The reaction with lithium aluminium hydride (LAH) results in an explosion. TFA is not biodegradable and is somewhat toxic to aquatic life - although it does not bioaccumulate, prevention of release into waterways is of extreme importance when using TFA Trifluoroacetic acid Trifluoroacetic acid (TFA) is an organofluorine compound with the chemical formula CFCOH. It is a structural analogue of acetic acid with all three of the acetyl group’s hydrogen atoms replaced by fluorine