Uranyl tungstates

Sodium tungstate 699 Sodium zinc uranyl acetate 467 Sol 419... 

According to C. F. Barwald and A. Monheim (1835), the decomposition is accelerated by the presence of organic substances. J. Milbauer tried the effect of thirty-two metal chlorides of sodium tungstate and molybdate of uranyl sulphate and of sulphuric, selenic, arsenic, and boric acids on the photo-decomposition of chlorine water, and found. that none accelerated but that most retarded the action. Chlorine catalyzes the decomposition of bromine water and bromine, chlorine water while iodine does not accelerate, but rather retards the reaction, probably by forming relatively stable iodine compounds. A. Bcnrath and H. Tuchel found the temp, coeff. of the velocity of the reaction with chlorine water between 5° and 30° increases in the ratio 1 1 395 per 10°. 

A characteristic example of case (b) is the uranyl ion (UO ). The Tie = 0— rig = 2 line dominates in the spectrum (Fig. 4b). The tungstate ion (WC)4 ) is a good example of case (c). The very broad emission spectrum (see Fig. 4c) does not show any vibrational structure at all, the Stokes shift is very large (—16,000 cm" ) and the zero-vibrational transition is not observable, not even at the lowest possible temperatures nor for the highest possible resolving powers. 

There are no doubts that, using variations of the U V ratio and chemical nature of the counter ions, many new compounds can be obtained with structures based upon six different building blocks described in the Introduction to this chapter. Other oxoanions with various geometries (tungstate and molybdate, for example) have already been used to build other frameworks. To compare these compounds with vanadates, we have initiated studies of uranyl niobates that should reveal new interesting topologies. 

M solution of Arsenazo I (Neothorin, Uranon, 3-(o-arsenophenylazo)-chromotropic acid), which gives a violet color with Th (blue with U) (Idn. Limit 5 y Th). Be, Cr+ , F, tungstate, vanadate, oxalate and silicate interfere with the detection of thorium. Uranyl salts can be extracted as diethyl-dithiocarbamate with benzene. ... 

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