Thermoneutral potential

The thermoneutral potential is 2.72 V this means that during charging at voltage below this value ZEBRA cells will be cooled thermodynamically. 

The energy required to break and to form molecular bonds and to bring reactants and products to their reference states is in fact measured by the enthalpy A H, vhich thus defines the so-called thermoneutral potential AE is used only for equilibrium quantities, while AVare potential differences away from equilibrium conditions) ... 

Thermoneutral potential — (Thermoneutral voltage) The voltage E given by... 

Reaction 15 is endothermic and the electrolyzed water will undergo self-cooling unless external heat is supplied. The enthalpy balance and its related thermoneutral potential, tneut, are given by ... 

A thermoneutral potential, tn( tn = AHh o/zF), is defined in which no heat turnover is observed and tn = 148 V for water electrolysis [16]. If, because of effective catalysis, the total electrolysis cell voltage is close to 1.48 V, then tielectrolysis 1-... 

The actual efficiency of the cell is defined as the actual voltage divided by the thermoneutral potential, that is,... 

V is the potential corresponding to hydrogen s higher heating value, or the thermoneutral potential. 

Fig. 4 Free energy reaction coordinate profiles that illustrate a change in the relative kinetic barriers for partitioning of carbocations between nucleophilic addition of solvent and deprotonation resulting from a change in the curvature of the potential energy surface for the nucleophile addition reaction. This would correspond to an increase in the intrinsic barrier for the thermoneutral carbocation-nucleophile addition reaction.

Fig. 2.6 Potential energy contour diagram for a thermoneutral reaction.

These features, together with the reversible, thermoneutral nature of the cyanohydrin formation, make the reaction potentially useful for applications in dynamic chemistry. This was also recently shown in a DCR study [4],... 

FIGURE 1. Double-well potential energy profile for a gas-phase ion-molecule reaction. The example shown refers to a thermoneutral reaction. 

CLs), resulting in a drastic drop in cell performance [17], Figure 3.13 also shows the difference between the theoretical cell potential (1.23 V) and the thermoneutral voltage (1.4 V), which represents the energy loss under reversible conditions (the reversible loss) [18], Very often, polarization curves are converted to power density versus current density plots by multiplying the cell voltage by the current density at each point of the curve. 

The redox potentials for the electron acceptors that react with HO (Table 15) are such that a pure outer-sphere single-electron transfer (SET) step would be endergonic (the HO /HO redox potential is more positive than the redox potential of the electron acceptor). Hence, the observed net reactions must be driven by coupled chemical reactions, particularly bond formation by the HO to the electrophilic atom of the acceptor molecule that accompanies a singleelectron shift. (The formation of the bond provides a driving force sufficient to make the overall reaction thermoneutral or exergonic 1.0 V per 23.1 kcalmol of bond energy.) The effect of various transition metal complexes on the oxidation potential for HO in MeCN illustrates some of these effects the results are summarized in Table 16. ... 

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