The Reactivity of Silver Atoms in Aqueous Solutions (A γ‐Radiolysis Study)

Abstract

Abstract Silver chloride and silver are the products of the γ‐irradiation of air‐free Ag + solutions (∼ 10 −3 M) containing chloroacetic acid (∼ 10 −3 M), hydrogen ions (1 M) and t‐butanol (∼ 10 −1 M). The products result from various reactions of the silver atoms formed in the attack of H atoms on Ag + ions. The free silver atom Ag o (aq), Ag + 2 , and agglomerated atoms Ag m+ n ( m < n ) are intermediates of silver formation whose redox potential increases with increasing agglomeration number n. Ag o (aq) and probably Ag + 2 transfer an electron to chloroform, and Ag o (aq) with less efficiency to chloroacetic acid and ethyl chloride. They also are able to reduce Cu 2+ ions. The Cu + ions initiate the reduction of Ag + to yield the metal without Ag o (aq) being an intermediate.—The formation of silver in γ‐irradiated 10 −3 M Ag + solutions containing alcohols was also studied. In the presence of t‐butanol, G (Ag metal ) amounts to 1.8. In the presence of i‐propanol, it is equal to 4.7. In a solution containing both acetone and i‐propanol, the formation of silver is slow and autocatalyzed. 1‐hydroxy‐alkyl radicals cannot reduce Ag + in a single electron transfer process. However, reduction of Ag m + n agglomerates (which have a more positive redox potential) is possible.