Potassium pentachloroaquomolybdate

The solution is next concentrated to one-half its volume at 70° by the use of a water pump, and then cooled in an ice bath. Small rhombic, red crystals of the potassium pentachloroaquomolybdate(III) form. These are subsequently filtered with suction and washed with 12 N hydrochloric acid and then with alcohol. The washings are allowed to run into the filtrate in the filter flask. The product is dried in a current of carbon dioxide or in vacuo. The yield is 19.0 g. (34.2%). Anal. Calcd. for K2[MoC15-H20] Mo, 26.0 Cl, 48.0. Found Mo, 25.3 Cl, 48.7. These results imply some contamination with K3[MoCle]. 

The physical properties of the aqueous solutions were studied by Bucknall and coworkers 14 Ray and Bharls studied the magnetic susceptibility of the hexachloro complex. Potassium pentachloroaquomolybdate(III) exists as rhombic crystals and is isomorphous with potassium pentachloroaquoferrate(III).16 Potassium hexachloromo-lybdate(III) has been used for the preparation of potassium hexathiocyanatomolybdate(III), potassium heptacyano-aquomolybdate(III),17and potassium octacyanomolybdate-(IV).18... 

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