Incompatibilities
Sodium arsenate reacts with moisture, steam, and water; forming flammable and toxic arsenic hydride. Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Sodium arsenate is a weak oxidizing agent that may react with reducing agents, including hydrides. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides, chemically active metals. Arsine, a very deadly gas, can be released in the presence of acid, acid mists; or hydrogen gas. Attacks many metals (such as aluminum, iron, and zinc) in presence of moisture producing arsenic and arsine fumes
Waste Disposal
Dissolve in minimum quantity of concentrated, reagent hydrochloric acid. Filter if necessary. Dilute with water until white precipitate forms. Add just enough 6M HCl to redissolve. Saturate with hydrogen sulfide. Filter, wash the precipitate; dry, package, and ship to the supplier.