Gamma scale chemistry progress report, May 1--31, 1948

An attempt has been made to prepare a compound of postum (Polonium 210) analogous to K{sub 2}{sup TeBr}{sub 6}. A preliminary experiment indicates possible preparation of bromides of postum and that these bromides are analogous to the chloride of postum. Photomicrographs of two crystalline forms of a product resulting from the reaction of bromine and postum are included in this report together with procedure used to form these crystals. Intermediate compounds formed in the attempted preparation of potassium postum bromide include a white residue from nitric acid containing postum and a yellow material formed on the ignition of this white residue. This yellow residue was identical in appearance to the yellow dioxide of postum. A red crystalline precipitate resulted when the yellow residue, which may well be QO{sub 2}, was treated with solution of hydrobromic acid and potassium bromide. Investigation of the use of titanium trichloride as a reducing agent to titrate, quantitatively tellurium dioxide has not yielded concordant results. An effort is being made to determine the best conditions for such a titration potentiometrically. Variations in concentrations, temperature of titration, electrode surface, acid concentration, and degree of agitation are in suspect