Die G‐Werte von H_aq⁺ und OH_aq⁻ in wäßriger Lösung

Abstract

Die Ausbeuten an Haq+ und OHaq− wurden nach der Pulsradiolyse von neutralem Wasser mit Hilfe einer Leitfahigkeitsmeßeinrichtung neu bestimmt. Die Werte in Argon‐gesättigter Lösung 0.5 μs nach einem 1 μs Bestrahlungsimpuls mit 2,8 MeV Elektronen sind: G(Haq+)Ar = (3.3 ± 0.25)/100eV, G(OHaq−)λr = 0.60 ± 0.25 (unter der Voraussetzung G(eaq−) = 2,7); mit 10−1 mol/1 Äthanolzusatz beträgt G(eaq−) = 3.2 (optisch gemessen), G(OHaq−) = 0.1 und G(Haq−) = 3,3. In N2O‐gesättigter Lösung betragen G(Haq+)N2O = G(OHaq−)N2O = 2,9 ± 0,25. Die Wirkungen der Zusätze werden als Spureffekte gedeutet.

Diffusion-kinetic calculations of the effect of nitrous oxide on the yields of ionic species in the radiation chemistry of water

“…If we take the total anion yield as the experimental number (3.35), then the yield for N20-saturated solutions at ~100 ns is estimated to be 3.0. Both Schmidt and Ander8 and Klever et al 7 give the OH" yields as 2.9.…”

“…Preliminary experiments4 using -naphthol to scavenge OH" indicate that the concentration of OH' on the 100-ns time scale corresponds to a yield of only -2.85.5 This yield is substantially less than that of ~3.35 which is measured for ion pairs in N20free water by time-resolved conductivity methods. 6,7 In fact, Schmidt and Ander8 as early as 1969 found that the ion pair yield on the microsecond time scale in N20-sa tura ted water was 2.9, which is 14% lower than in argon-saturated water. Klever et al 7 found a similar result and suggested that spur processes were responsible for the observed difference.…”

“…6,7 In fact, Schmidt and Ander8 as early as 1969 found that the ion pair yield on the microsecond time scale in N20-sa tura ted water was 2.9, which is 14% lower than in argon-saturated water. Klever et al 7 found a similar result and suggested that spur processes were responsible for the observed difference. More recently, Anderson et al9 compared the conductance of argon-and N20-sa tura ted solutions at 100 ns and also found a similar reduction at the earlier time.…”