::4 AsCl3 + 3 NaBH4 → 4 AsH3 + 3 NaCl + 3 BCl3As reported in 1775, Carl Scheele reduced arsenic(III) oxide with zinc in the presence of acid.
AsH3 je piramidasta molekula z H–As–H s kotom 91.8° in s tremi enakovrednimi As-H vezmi, vsak z dolžino 1,519 Å.