Triflic acid acid and its conjugate base CFSO, known as triflate, resist oxidation/reduction reactions, whereas many strong acids are oxidizing, e.g. perchloric or nitric acid. Further recommending its use, triflic acid does not sulfonate substrates, which can be a problem with sulfuric acid, fluorosulfuric acid, and chlorosulfonic acid. Below is a prototypical sulfonation, which HOTf does "not" undergo: Triflic acid fumes in moist air and forms a stable solid monohydrate, CFSOH·HO, melting point 34 °C. The triflate ligand is labile, reflecting its low basicity. Trifluoromethanesulfonic acid exothermically reacts with metal carbonates, hydroxides, and oxides. Illustrative is the synthesis of Cu(OTf). Chloride ligands
Hydrazoic acid lithium) or alkaline earth metals are not explosive, but decompose in a more controlled way upon heating, releasing spectroscopically-pure gas. Solutions of hydrazoic acid dissolve many metals (e.g. zinc, iron) with liberation of hydrogen and formation of salts, which are called azides (formerly also called azoimides or hydrazoates). Dissolution in the strongest acids produces explosive salts containing the ion, for example: The ion is isoelectronic to diazomethane. The decomposition of hydrazoic acid, triggered by shock, friction, spark, etc. goes as follows: Hydrazoic acid is volatile and highly toxic. It has a pungent smell and its vapor can cause violent headaches.