Abstract
Redox couples formed with Fe{sub 2}O{sub 3}/Fe{sub 3}O{sub 4}, FeO{sub 2}H/Fe{sub 3}O{sub 4}, NiO/Ni, Cu{sub 2}O/Cu, Ag{sub 2}O/Ag, HgO/Hg and Sb{sub 2}O{sub 3}/Sb, in borax buffer solution have been studied at temperatures up to 100 deg C. The composition and morphology of the solid phases were characterized by X-ray diffraction measurements and electron micrography. Electrodes were formed with beds of mixtures of the solids through which the electrolyte was slowly perculated, and their potentials were measured relative to the hydrogen electrode. The results show that, in weakly alkaline solutions, systems including these couples only slowly attain electrochemical equilibrium. In the case of the iron couples at 25 deg C, for example, an emf with a long-term stability within 0.1 mV is not attained until after more than eight days equilibration: At higher temperatures a stable emf is attained more rapidly. All of the electrodes except the NiO/Ni electrode seem to be reversible but only the HgO/Hg electrode and, perhaps, the Cu{sub 2}O/Cu and Ag{sub 2}O/Ag electrodes, are likely to be useful at elevated temperatures. The apparent equilibrium constants found for the electrode reactions are compared with the theoretical values
Citation Formats
Johansson, Karin, Johnsson, Kerstin, and Lewis, Derek.
Studies of Redox Equilibria at Elevated Temperatures 3. Oxide/oxide and Oxide/metal Couples of Iron, Nickel, Copper, Silver. Mercury and Antimony in Aqueous Systems up to 100 deg C.
Sweden: N. p.,
1973.
Web.
Johansson, Karin, Johnsson, Kerstin, & Lewis, Derek.
Studies of Redox Equilibria at Elevated Temperatures 3. Oxide/oxide and Oxide/metal Couples of Iron, Nickel, Copper, Silver. Mercury and Antimony in Aqueous Systems up to 100 deg C.
Sweden.
Johansson, Karin, Johnsson, Kerstin, and Lewis, Derek.
1973.
"Studies of Redox Equilibria at Elevated Temperatures 3. Oxide/oxide and Oxide/metal Couples of Iron, Nickel, Copper, Silver. Mercury and Antimony in Aqueous Systems up to 100 deg C."
Sweden.
@misc{etde_922508,
title = {Studies of Redox Equilibria at Elevated Temperatures 3. Oxide/oxide and Oxide/metal Couples of Iron, Nickel, Copper, Silver. Mercury and Antimony in Aqueous Systems up to 100 deg C}
author = {Johansson, Karin, Johnsson, Kerstin, and Lewis, Derek}
abstractNote = {Redox couples formed with Fe{sub 2}O{sub 3}/Fe{sub 3}O{sub 4}, FeO{sub 2}H/Fe{sub 3}O{sub 4}, NiO/Ni, Cu{sub 2}O/Cu, Ag{sub 2}O/Ag, HgO/Hg and Sb{sub 2}O{sub 3}/Sb, in borax buffer solution have been studied at temperatures up to 100 deg C. The composition and morphology of the solid phases were characterized by X-ray diffraction measurements and electron micrography. Electrodes were formed with beds of mixtures of the solids through which the electrolyte was slowly perculated, and their potentials were measured relative to the hydrogen electrode. The results show that, in weakly alkaline solutions, systems including these couples only slowly attain electrochemical equilibrium. In the case of the iron couples at 25 deg C, for example, an emf with a long-term stability within 0.1 mV is not attained until after more than eight days equilibration: At higher temperatures a stable emf is attained more rapidly. All of the electrodes except the NiO/Ni electrode seem to be reversible but only the HgO/Hg electrode and, perhaps, the Cu{sub 2}O/Cu and Ag{sub 2}O/Ag electrodes, are likely to be useful at elevated temperatures. The apparent equilibrium constants found for the electrode reactions are compared with the theoretical values}
place = {Sweden}
year = {1973}
month = {Aug}
}
title = {Studies of Redox Equilibria at Elevated Temperatures 3. Oxide/oxide and Oxide/metal Couples of Iron, Nickel, Copper, Silver. Mercury and Antimony in Aqueous Systems up to 100 deg C}
author = {Johansson, Karin, Johnsson, Kerstin, and Lewis, Derek}
abstractNote = {Redox couples formed with Fe{sub 2}O{sub 3}/Fe{sub 3}O{sub 4}, FeO{sub 2}H/Fe{sub 3}O{sub 4}, NiO/Ni, Cu{sub 2}O/Cu, Ag{sub 2}O/Ag, HgO/Hg and Sb{sub 2}O{sub 3}/Sb, in borax buffer solution have been studied at temperatures up to 100 deg C. The composition and morphology of the solid phases were characterized by X-ray diffraction measurements and electron micrography. Electrodes were formed with beds of mixtures of the solids through which the electrolyte was slowly perculated, and their potentials were measured relative to the hydrogen electrode. The results show that, in weakly alkaline solutions, systems including these couples only slowly attain electrochemical equilibrium. In the case of the iron couples at 25 deg C, for example, an emf with a long-term stability within 0.1 mV is not attained until after more than eight days equilibration: At higher temperatures a stable emf is attained more rapidly. All of the electrodes except the NiO/Ni electrode seem to be reversible but only the HgO/Hg electrode and, perhaps, the Cu{sub 2}O/Cu and Ag{sub 2}O/Ag electrodes, are likely to be useful at elevated temperatures. The apparent equilibrium constants found for the electrode reactions are compared with the theoretical values}
place = {Sweden}
year = {1973}
month = {Aug}
}