17:2-Tungsto-arsenates

Solutions of the 9-tungsto-arsenates, when treated with the corresponding carbonates until the yellow colour disappears, yield colourless crystalline precipitates of salts belonging to this series, isomorphous with the corresponding phosphates and of composition 5(NH₄)₂O.As₂O₅.17WO₃.16H₂O and 5K₂O.As₂O₅.17WO₃.22H₂O.