Absorption spectra were determined for various times after a 10hyphen;nsec radiation pulse to 0.1MHClO4solutions containing AgClO4with and withoutterthyphen;butyl alcohol (TBA). The spectra and their time dependence, which show the same features at 1 atm and 6.6 kbar, are interpreted in terms of the following reactions: H plus; Agplus;rarr; Hplus;plus; Ag 2, OH plus; Agplus;rarr; OHminus;plus; Ag2plus;5, Ag plus; Agplus;rarr; Ag2plus;6. Scavenging of OH by TBA prevents formation of Ag2plus;which has an absorption peak near 270 nm. For solutions containing TBA, a 60hyphen;nsec spectrum with a peak at 370 nm is assigned to Ag and a 7hyphen;mgr;sec spectrum with a peak at 310 nm and shoulder at 260 nm is assigned toAg2plus;. Growth and decay of Ag absorption at 410 nm were studied with solutions containing TBA at 29 deg;C and six pressures in the range 1 atmndash;6.7 kbar; the reactions of H with glycerol and ethylene glycol were studied by their competition with Reaction 2 in solutions also containing glycerol or ethylene glycol. The results give atmospherichyphen;pressure specific rates of 2.8 times; 1010, 3.8 times; 107, and 1.9 times; 107Mminus;1middot;secminus;1and pressurehyphen;independent activation volumes of 1.7, minus; 5.0, and minus; 4.2 ml molminus;1for the reactions of H with Agplus;, glycerol, and ethylene glycol, respectively. Results of this study and a previous ggr;hyphen;radiolysis study are combined to give best values of (1) Dgr;VDagger;equals; 2 ml molminus;1for the diffusionhyphen;controlled reactions of H with Agplus;and O2and (2) Dgr;VDagger;equals; minus; 5 ml molminus;1for each of 15 presently studied reactions of H not controlled by diffusion. From such results it is concluded that (1) diffusion of H is governed in some manner by the viscosity of water and (2)Vmacr;(H) equals; 5 ml molminus;1and is incompressible.
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