Carbon dissodation

The residual dissodation of the zwitter ion and the background conductance of the eluent is even lower than for the carbonate/bicarbonate system, if amino acids are selec-... 

The island mechanism assumes that adsorption takes place in wet conditions and H2O adsorbed on the carbon surface, is able to create water clusters or small water islands, where MM and oxygen first are dissolved in molecular form and later, depending on the pH, MM can dissociate to thiolate ion. Oxidation occurs due to the surface reaction between adsorbed thiolate ions and dissodatively adsorbed oxygen in water "islands" and/or between adsorbed MM and oxygen on a dry part of the carbon surfece. The product of reaction, DMDS, is adsorbed in a molecular form on the carbon surface (Fig. 35). 

Methane, acetic acid, acetaldehyde, and ethanol constitute approximately 90 carbon atom percent of the primary products from the hydrogenation of CO over Rh/SiO and Rhr-Mn/SiOi catalysts at 250 -300°C and 30-200 atm pressure in a back-mixed reactor with H /CO = 1. The rate of reaction and the ratio, CHj /C chemicals, vary with (Pjy / The addition of 1% Mn raises the synthesis rate of a 2.5% Rh/SiOfi catalyst about tenfold. The kinetics and the product distribution are consistent with a mechanism in which CO is adsorbed both associatively and dissodatively. The surface carbon produced by the dissociative CO chemisorption is hydrogenated through a Rh-CHs intermediate, and CO insertion in that intermediate results in formation of surface acetyl groups. 

Homocysteine lactonizes readily in acidic solutions, and a study of the aqueous radiation chemistry of this thiolactone was undertaken to see how bonding of the sulphur to a carbonyl carbon modifies its reactivity to the aquated electron . (The normal H atom abstraction from sulphur by OH cannot occur.) The dissodative electron capture reaction which gives H S in the case of free thiols can be formulated ... 

The atmosphere contains 0.03% (by volume) CO2. The partial pressure of the gas under normal aerobic conditions is 3 x 10 atm. The solubility of CO2 at 25 °C in pure water (it is decreased by the presence of salts) is 0.0344 M under 1 atm of the gas and 10.35 pM under aerobic conditions (if these can still be regarded as standard). The total carbon dioxide content of a solution in equilibrium with a given pressure of gas is given by the sum of the concentrations of CO2, H2CO3, and HCOf. The distribution between these species is pH dependent. The second add dissodation constant... 

Gibson, Q. H. Roughton, F. J. W. (1957). The determination of dissodation of the velocity constants of the four successive reactions of carbon monoxide with sheep haemoglobin. Proceedings of the Royal Society of London, B146, 206-24. 

The compound dissolves in benzene, with dissodation. By leaving the benzene solution in the air, (carbonato)bis(triphenylphosphine)platinum(II) separates slowly. It reacts easily with carbon tetrachloride giving cts-dichlorobis(triphenylphosphine)platinum(IIX The complex is tricoordinated in the solid state, and shows a nearly pure sp hybridization of the platinum atom. ... 

The redox isomerization of the platinum(iv) compound (50) to the plati-num(n) compound (51), in benzene solution, is thought to be dissodative in mechanism. The intermediate (52), which can either re-form (50) or undergo platinum-carbon bond cleavage, is suggested. ... 

In water Xd cannot be longer than 960 nm. Due to the dissociation of water (according to 2H2O H3O+ + OH ), the ion concentration cannot decrease below 1 X 10 M. Practically, the Debye length even in distilled water is only a few 100 nm. One reason is dissolved CO2 that is converted to carbonic add and is partially dissodated ... 

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