Arsine

Arsine is the chemical compound with the formula AsH3. This flammable, pyrophoric, and highly toxic gas is one of the simplest compounds of arsenic. Aside from its lethality, it finds applications in the semiconductor industry and for the synthesis of organoarsenic compounds. At its standard state, arsine is a colorless, denser-than-air gas that is soluble in water (200 mL/L) and in many organic solvents as well. Whereas arsine itself is odorless, owing to its oxidation by air it is possible to smell a slight, garlic-like scent when the compound is present at about 0.5 ppm. This compound is generally regarded as stable, since at room temperature it decomposes only slowly. At temperatures of ca. 230 °C decomposition to arsenic and hydrogen is rapid. Several factors, such as humidity, presence of light and certain catalysts (namely aluminium) facilitate the rate of decomposition.