Voltages calculated

It can be seen that Mn02 will oxidize to Fe+, H2 (if any is around) to H+, and Fe to Fe+, then on to Fe+. Appropriate equations may be written for these reactions, and voltages calculated by differences. Mn02 appears as the lower species on the Mn04 /Mn02 rung, which means that it will react with the upper species on any rung above it, and there is none. 

From this voltage, calculate the equilibrium constant for the reaction Hg2+ + 41 - lignin 0.5 M KI, virtually all the mercury is present as Hgl. ... 

The voltage at zero titrant volume cannot be calculated, because we do not know how much Fe3+ is present. If [Fe3+] = 0, the voltage calculated with Equation 16-6 would be —... 

Figure 16. The surface layer of water, in one unit cell, at one instant during the zero applied voltage calculation. The large, light blue spheres represent the surface layer of the cadmium slab. From Ref. 52, by permission.

Additional explanatory material is added throughout the book. Some of the material explains further and simplifies concepts under discussion, while other material adds new information. In Chapter 2 paint pigments and binders are discussed. New information on surprising origins of ancient paint pigments and binders is added. In Chapter 3 supports for paints are described, and information is added about supports used in 50 B.C. that are still used today. In Chapter 6, in which jewelry making and the study of metals and electrochemistry are combined, an electromotive series is added to enhance cell voltage calculations. 

Hegedus et al. [146] also measured the I-V curves of amorphous Si p-i-n solar cells at different temperatures. The curves in the dark and also under illumination are shown in Fig. 5.25. The I-V curves under illumination obey Eq. (5.8) in this case also. The built in voltage calculated from the illuminated curves was satisfactory. Hegedus et al. [146] took small portion of the dark I-V curves which could be represented by an equation of the type (5.5). They then attempted to derive the built in voltage using this dark current as Shockley currents. They obtained very strange results. Hegedus et al. [146] wrote Our results also clearly demonstrate that it is completely inappropriate to analyze J( V) data measured in the dark on a-Si p-i-n devices and then attempt to correlate the results with photovoltaic performance Measurements in the dark are not applicable to understand-... 

Hydrogen ion concentration of the equilibrated aqueous phase. b Reference voltage calculated by Equation 9. c Calculated by Nernst Equation. 

The temperature dependence of the theoretical efficiencies AG°/AH° of various reactions are plotted on the right scale. The corresponding cell voltages calculated from the Nernst equation are shown as well (left scale). 

For cell voltage calculations, assume that the temperature is 25°C unless stated otherwise. 

For methanol as fuel, the cell voltage calculated from thermodynamic data is 1.215 V, but here in practice open circuit voltages of about 0.7 V are achieved and... 

In the first case, two electrons are transferred per mercury ion (n = 2), while in the second only one is transferred ( = 1). Note that the concentration ratio will be 1 10 in both cases. The voltages calculated at 18°C are ... 

There are the many open circuit emf studies that have been carried out to search for new solid electrolyte materials. The specimen is placed in contact with electrodes which establish different but known partial pressures Px2 Px2 measured. The ratio of the measured emf E to the thermodynamic voltage calculated from Equation 7 gives a quick estimate of the materials ionic transference number, as implied by Equation 6 cibove. This is an estimate to be sure, because the ratio actually averages the value of tj over the scale. But the method very quickly reveals which materials might best be ruled out for further studies. Indeed, those which persist in registering a zero measured emf are predominantly electronic conductors and probably not much can be done (e.g., by way of doping etc.) to make them into ionic conductors, i.e., solid electrolytes. 

Compare the potentials, as measured in this experiment, for the oxidation-reduction reactions which occurred in the three galvanic cells with the standard voltages calculated from standard reduction potentials. Suggest possible reasons for any differences. 

The thermodynamic decomposition voltages calculated above are the equilibrium cell voltages when there is no applied current. When current passes, the system departs from equilibrium conditions to drive the reactions. The cell voltage will then he higher than the thermodynamic decomposition voltage because of the overvoltages associated with the anodic and cathodic reactions and the ohmic drops. 

The voltage at zero titrant volume cannot be calculated because we do not know how much Fe is present. If [Fe ] = 0, the voltage calculated with Equation 16-9 would be -00. In fact, there must be some Fe in each reagent, either as an impurity or from oxidation of Fe by atmospheric oxygen. In any case, the voltage could not be lower than that needed to reduce the solvent (H2O + e —> H2 + OH ). 

The difference in the Nernst voltages calculated by using the partial pressures of the reacting gas species at the bulk and the TPB gives the concentration overvoltage. The reversible Nernst voltage of the cell is represented in terms of the species partial pressures and temperature as... 

Figure 6.6 Schematic depiction of source and drain currents versus average of source and drain potentials (gate potential) when the source and drain potentials are changed simultaneously while maintaining a fixed potential offset between them (source-drain voltage) calculated using Equation 6.10 (i.e., gate measurement) [7], Lines labeled a-g indicate source and drain current for different gate potentials. The source-drain voltage used here to calculate the source and drain current is 0.1 V.

Figure 6.8 Schematic depiction of source and drain currents versus gate potential for different source-drain voltages calculated using Equation 6.10.

Figure 1.11.4 Energy efficiency for given CEasa function of cell voltage (calculated from thermodynamic data)...

Fig. 9—Electro-optic transfer coefficient along surface orientation for twisted structure. With the source (S) in a plane perpendicular to the electrodes and parallel to the optic axis of the nematic orientation at that electrode, the optical transmission is a monotonic function of angle and voltage (calculated curves). ...

Table 2.6 shows the maximum voltages calculated by the frequency-dependent Semiyen model and the frequency-independent distributed parameter line model of the EMTP. It is clear from Figure 2.45 and Table 2.6 that the results neglecting the frequency-dependent effect show a mi-nor difference from the results including the effect. Thus, it can be con-cluded that the frequency-dependent model does not have a significant effect on a lightning surge. 

Calculated transient voltage (a) 66 kV bus voltages and (b) 22 kV bus voltages. Calculated transient voltage (c) Bank-A voltages and (d) Bank-B voltages. 

Calculate the energy density (Wh kg ). The energy density can then be obtained by multiplying the specific capacity obtained from calculating the specific capacity with the thermodynamic voltage calculated when... 

Figure 2.8 Efficiency of fuel cells (fraction of the change in the oxygen Gihbs enthalpy which is turned into useful energy) versus the quotient load voltage open-circuit voltage ----------------------------, calculated using an equivalent circuit (1958-1967) -------calculated using transport equations (1978-1981).

Calculated average voltage of L1JV1B03 (M = Mn, Fe, Co) versus Li as a function of various U values. Dashed circles indicate the average voltages calculated with Up values. (Adapted with permission from D.-H. Seo et al.. First-principles study on lithium metal borate cathodes for lithium rechargeable batteries, Phys. Rev. B 83,2011,205127. Copyright 2011, American Physical... 

Based on the advanced approach, fuel cell losses are estimated and are shown in Fig. 5.11. The maximum voltage calculated for partial pressures taken at both the anode and cathode outlets gives adequate shape according to both activation and concentration (diffusion) losses. The rest losses are generated by the two resistances represent. The influence of electrical resistance (r2) occurs mainly at the start of the fuel cell operation curve. In the advanced model, the losses can be defined separately for each layer making up the cell. From Fig. 5.11, it is clear that... 

---