Ion-proton exchange

Kurbatov plots (jj ) have often been employed to determine the net metal ion/proton exchange, x> from adsorption data. Although Kurbatov constants are convenient curve-fitting parameters, they are insensitive to the variation of x with pH and adsorption density and should be dispensed with for use in adsorbate partitioning calculations, particularly when high adsorption densities are expected ( 9 ). 

Because the inner mitochondrial membrane is impermeable to protons and other ions, special exchange transporters span the membrane to allow passage of ions such as OH, Pf, ATP , ADP, and metabo-htes, without discharging the electrochemical gradient across the membrane. 

Membrane-type fuel cells. The electrolyte is a polymeric ion-exchange membrane the working temperatures are 60 to 100°C. Such systems were first used in Gemini spaceships. These fuel cells subsequently saw a rather broad development and are known as (solid) polymer electrolyte or proton-exchange membrane fuel cells (PEMFCs). 

Equilibria Where a Neutral Molecule Is Exchanged. The difficulties discussed above for proton transfer and electron transfer equilibria involving multiply charged ions are not present when neutral molecules (ligands) which are complexed to a given ion are exchanged. Equation 43 is a typical example ... 

Water and Proton Exchange Processes on Metal Ions... 

Ammonium and hydrogen ions (protons) are both present in the soil solution as multielement cations. Ammonia gas reacts with water to produce the ammonium cation, NH4+ (Figure 5.8, equation 1). Ammonium acts as a cation in all senses and will be attracted to cation exchange sites on soil particles. Ammonium in the soil solution and on exchange sites is available to plants. 

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