Potassium Trimolybdate, K₂Mo₃O₁₀.3H₂O

Potassium Trimolybdate, K₂Mo₃O₁₀.3H₂O, is often produced, either spontaneously or by the action of water, from other molybdates. It may be prepared by fusing one molecular proportion of potassium carbonate with two of molybdic anhydride; the aqueous extract of the fused mass deposits crystals of the trimolybdate. Another method of preparation consists in saturating boiling potassium carbonate solution with molybdenum trioxide, filtering, and allowing the solution to stand. The salt forms silky needles which become anhydrous at 100° C., and are less soluble in water than the corresponding sodium salt.