Potassium tetraoxalatouranate

Potassium tetradecaehlorotritung-state(III), K5W3CU4, 6 149,153 Potassium tetrafluoroborate, 1 24 Potassium tetraoxalatouranate(IV), 3 169... 

Tris(2,4-pentanedionato)molybdenum(III), synthesis 39 Potassium tetraoxalatouranate(IV), synthesis 40 Trifluoromethyl hypofluorite, synthesis 42 Bis(ethylenediamine)dioxorhenium(V) chloride, bis(ethylene-diamine)oxohydroxorhenium(V) perchlorate, and bis(ethyl-enediamine)dihydroxorhenium(V) hexachloroplatinate(IV), synthesis 44... 

Uranium(lV) oxalate, synthesis 45 Potassium tetraoxalatouranate (IV), synthesis 46 Barium thiocyanate, synthesis 5 Potassium octacyanomolybdate (IV) 2-hydratc, synthesis 43 Bis(lV,lV -disallcylalethylenedia-mine)-/t-aquodicobalt(II), synthesis 53... 

Potassium tetraoxalatouranate(IV) 5-hydrate has been prepared by the reaction of a potassium oxalate solution with an excess of uranium(IV) oxalate 6-hydrate.This excess prevents contamination of the product by potassium oxalate, since both potassium tetraoxalatouranate(IV) and potassium oxalate are precipitated from aqueous solution by absolute alcohol. 

A solution of 5 g. (0.027 mol) of potassium oxalate 1-hydrate in 20 ml. of water is added to a slurry of 6 g. (0.014 mol) of uranium(IV) oxalate 6-hydrate in 50 ml. of water. The reaction is complete after the mixture has been heated on a steam bath for 1 hour. The dark green filtrate is treated with 200 ml. of absolute alcohol, which is added drop by drop from a separatory funnel while the mixture is stirred. J Small light green crystals are obtained, which are quickly dried by washing them several times with absolute alcohol and finally with ether. To avoid oxidation, potassium tetraoxalatouranate(IV) is stored in a desiccator over phosphorus (V) oxide. 

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