Fulminates are chemical compounds which include the fulminate ion. The fulminate ion is a pseudohalic ion because its charge and reactivity are similar to those of the halogens. Due to the instability of the ion, fulminate salts are friction-sensitive explosives. The best known is mercury(II) fulminate, which has been used as a primary explosive in detonators. Fulminates can be formed from metals, such as silver and mercury, dissolved in nitric acid and reacted with ethanol. The weak single nitrogen-oxygen bond is responsible for their instability. Nitrogen very easily forms a stable triple bond to another nitrogen atom, forming nitrogen gas.