Abstract
Well refined 10 -65×10-5M dithizone-carbon tetrachloride is prepared, and a definite amount after standing for a certain number of days is shaked with excessive silver solution containing 110Ag tracer. The solvent layer is separated and its radioactivity is estimated. Similarly, carbon tetrachloride solutions consisting of dithizone and silver salt, and that of silver salt in excess of dithizone are allowed to stand for certain number of days, and the stability from aging is estimated by determining their radioactvities. A dilute solution of dithizone is completely decomposed by standing in a room for one month. The silver salt at a concentration of about 10-5M in the presence of dithizone in excess is very stable, but that of 10-6M is not especially stable even in the presence of an excessive amount of dithizone. The decomposition by exposing it to light is very rapid. If kept in the dark, it is fairly stable but there is no great difference from that kept in a room. Also there is no great difference in the stability of solutions prepared by using either first grade or further purified carbon tetrachlorides.
