Potassium tris , trihydrate

Potassium tris(malonato)chromate(IIl) trihydrate can be prepared by the method of Lapraik, reacting freshly precipitated chromium(III) hydroxide with malonic acid and potassium carbonate. Lapraik obtained the crystals by drying the aqueous solution over sulfuric acid, but the crystals are more easily obtained by precipitation in ethanol. 

Potassium tris(malonato)chromate(IlI) trihydrate is a blue-green compound which is very soluble in water. The cis isomer of potassium diaquabis(malo-nato)chromate(III) trihydrate is purple and also very soluble in water. The trans isomer is violet and fairly soluble in water, but it is more soluble than the analogous oxalate compound. All three compounds exhibit two absorption maxima in their visible absorption spectra, listed in Table I. 

PURPOSE OP EXPERIMENT Prepare potassium tris(oxalato)ferrate(III) trihydrate, K3[Fe(C204)3] 3H2O, and analyze it for oxalate ion and iron. 

C6H5AIK3O15, Potassium tris(oxalato)aluminate trihydrate, 44B, 864... 

Cerous iodates and the iodates of the other rare earths form crystalline salts sparingly soluble in water, but readily soluble in cone, nitric acid, and in this respect differ from the ceric, zirconium, and thorium iodates, which are almost insoluble in nitric acid when an excess of a soluble iodate is present. It may also be noted that cerium alone of all the rare earth elements is oxidized to a higher valence by potassium bromate in nitric acid soln. The iodates of the rare earths are precipitated by adding an alkali iodate to the rare earth salts, and the fact that the rare earth iodates are soluble in nitric acid, and the solubility increases as the electro-positive character of the element increases, while thorium iodate is insoluble in nitric acid, allows the method to be used for the separation of these elements. Trihydrated erbium iodate, Er(I03)3.3H20, and tri rated yttrium iodate, Yt(I03)3.3H20,... 

Tris[benzenetelIurolato]rhodiuin A solution of 0.415 g (1.58 mmol) of rhodium trichloride trihydrate in 40 ml of hot ethanol is added to a boiling solution of 4.5 g (15.9 mmol) of diphenyl tellurium in 160 ml of ethanol. To this mixture are added in sequence 16 w/ of 40% aqueous formaldehyde and a solution of 1.28 g of potassium hydroxide in 40 ml of hot ethanol. The resultant mixture is heated under reflux for 30 min, cooled to 20°, and the dark brown solid is filtered yield 0.95 g (84%) dec. 155°. 

These crystal-structure analyses are concerned with the following molecules o-D-glucopyranose monohydrate/ D-xylopyranose/ methyl yS-D-xylopyranoside, di-jS-n-fructopyranose-strontium chloride trihydrate, cellobiose (independent determination), D-glucaric acid, D-galactonic acid, methyl a-D-lyxofuranoside, /3-D-lyxopyranose, methyl 3,4,6-tri-0 - acetyl - 2 - (chloromercuri) - 2 - deoxy - j3 - d - glucopyranoside, D-glu-copyranosyl (potassium sodium phosphate) tetrahydrate," and methyl 6-bromo-6-deoxy-a-D-galactopyranoside. ... 

Elemi gum Lead acetate Lead acetate trihydrate Lithium stearate Polymethylhydrosiloxane Potassium alum anhydrous Pyridine Sodium alum Tallow acid 1,2,4,5-Tetrachlorobenzene Tri-m-cresyl phosphate Tri-p-tolyl phosphate Zinc acetate Zinc ricinoleate waterproofing agent mfg. 

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