C₆H₅AsCl₂, a colorless liquid with a melting point of –20°C and a boiling point of 257°C (with decomposition). Phenyldichloroarsine has a density of 1.625 g/cm³ (20°C) and a volatility (maximum concentration) of 0.274 mg/liter (20°C). The compound irritates the upper respiratory tract, inducing uncontrollable sneezing and coughing; it also has vesicant and resorptive effects. Phenyldichloroarsine is insoluble in water but readily soluble in most organic solvents. It can be obtained by the action of SO₂ on phenylarsenic acid in concentrated hydrochloric acid. The compound was used as a war gas in World War I.