caa a22 4500 465732674 CHVBK 20180323111745.0 cr unu---uuuuu 170327e19901201xx s 000 0 eng 10.1007/BF02039609 doi (NATIONALLICENCE)springer-10.1007/BF02039609 Temperature and ionic strength influence on U(VI/V) and U(IV/III) redox potentials in aqueous acidic and carbonate solutions [Elektronische Daten] [H. Capdevila, P. Vitorge] Redox potentials: E(UO 2 2+ /UO 2 + )=60±4 mV/NHE, E(U4+/U3+)=−630±4mV/NHE measured at 25°C in acidic medium (HClO4 1M) using cyclic voltametry are in accordance with the published data. From 5°C to 55°C the variations of the potentials of these systems (measured against Ag/AgCl electrode) are linear. The entropies are then constant: [ΔS(UO 2 2+ /UO 2 + )−ΔS(Ag/AgCl)]/F=0±0.3 mV/°C, [ΔS(U4+/U3+)−ΔS(Ag/AgCl)]/F=1.5±0.3 mV/°C. From 5°C to 55°C, in carbonate medium (Na2CO3=0.2M), the Specific Ionic Interaction Theory can model the experimental results up to I=2M (Na+, ClO 4 − , CO 3 2− ): E(UO2(CO3) 3 4− /UO2(CO3) 3 5− )=−778±5 mv/NHE (I=0, T=25°C, Δ∈(25°C)=∈(UO2(CO3) 3 4− , Na+)−∈(UO2(CO3) 3 5− , Na+)=0.92 kg/mole, ΔS(UO2(CO3) 3 4− /UO2(CO3) 3 5− =−1.8±0.5 mV/°C (I=0), Δ∈=∈(Cl−, Na+)=(1.14−0.007T) kg/mole. The U(VI/V) potential shift, between carbonate and acidic media, is used to calculate (at I=0,25°C): $$\log \frac{{\beta _3 U(V)}}{{\beta _3 U(VI)}} = - 14.7 \pm 0.5$$ and then $$\log \beta _3 U(V) = 6.6 \pm 0.3.$$ Akadémiai Kiadó, 1990 Capdevila H. Laboratoire de Chimie CEA IRDI/DERDCA/DRDD/SESD/SCPCS, 92265, Fontenay aux Roses, Cedex, France aut Vitorge P. Laboratoire de Chimie CEA IRDI/DERDCA/DRDD/SESD/SCPCS, 92265, Fontenay aux Roses, Cedex, France aut Journal of Radioanalytical and Nuclear Chemistry Kluwer Academic Publishers 143/2(1990-12-01), 403-414 0236-5731 143:2<403 1990 143 10967 https://doi.org/10.1007/BF02039609 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02039609 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Capdevila H. Laboratoire de Chimie CEA IRDI/DERDCA/DRDD/SESD/SCPCS, 92265, Fontenay aux Roses, Cedex, France aut NATIONALLICENCE 700 1- Vitorge P. Laboratoire de Chimie CEA IRDI/DERDCA/DRDD/SESD/SCPCS, 92265, Fontenay aux Roses, Cedex, France aut NATIONALLICENCE 773 0- Journal of Radioanalytical and Nuclear Chemistry Kluwer Academic Publishers 143/2(1990-12-01), 403-414 0236-5731 143:2<403 1990 143 10967 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer