Electrolytes paste

Uses and Economic Aspects. Magnesium bromide is used in medicine as a sedative in treatment of nervous disorders, in electrolyte paste for magnesium dry cells, and as a reagent in organic synthesis reactions. The price of magnesium bromide hexahydrate in January 1995 was 5.51/kg (33). 

Modern dry cells are closely modelled on the Leclanche cell, and also contain electrolyte pastes. You have probably used dry cells in all kinds of applications, such as lighting a flashlight, powering a remote control, or ringing a doorbell. Dry cells are inexpensive. The cheapest AAA-, AA-, C-, and D-size 1.5-V batteries are dry cells. 

Two common types of button batteries both use a zinc container, which acts as the anode, and an inert stainless steel cathode, as shown in Figure 11.11 on the next page. In the mercury button battery, the alkaline electrolyte paste contains mercury(II) oxide, HgO. In the silver button battery, the electrolyte paste contains silver oxide, Ag20. The batteries have similar voltages about 1.3 V for the mercury cell, and about 1.6 V for the silver cell. 

Overbeek, J. Th. G. (1976) Poly electrolytes. Past, Present and Future, Pure Appl. Chem. 46, 91-101. 

The administration of plain water is of minimal benefit to restore plasma volume in horses exercised in hot and humid conditions (Marlin et al 1998). However, the administration of an ORS or an electrolyte paste together with the provision of fresh drinking water may be sufficient to supplement water and electrolytes following vigorous or prolonged exercise in dehydrated horses with orily mild hypovolemia (Marlin et al 1998, Sosa Leon et al 1998). 

FIGURE 19.7 Interior section of a dry cell of the kind used in flashlights and transistor radios. Actually, the cell is not completely dry, as it contains a moist electrolyte paste. 

Maxima of the first kind. These appear as sharp straight line enhancements in the current at the beginning of the wave. They can be larger than the wave itself and drop abruptly back to the wave maximum. They are due to convective streaming of the electrolyte past the drop surface caused by differences in surface tension at different points of the drop surface. 

M. B. Armand, J. M. Chabagno, M. J. Duclot, Polyethers as solid electrolytes, Past Ion Transparent Solids Electrodes Electrolytes, Proceedings of the International Conference 1979, 131. 

It was found that electropolishing occurs in systems which, under anodic dissolution, exhibit a limiting current characteristic of diffusion control, i.e., currents are dependent on flow rate of the electrolyte past the anode, as shown in Figure 24. Over a certain range of potentials at the limiting current plateau, at which maximum brilliance is obtained, oscillations of potential occur at a virtually constant current density, with an amplitude of over 0.40 V, and without appreciable damping. Also, a significant photoelectrochemical effect is found. 

KOH makes the electrolyte paste in this battery basic. Thus, it is called an alkaline dry cell. 

Figure 3.2 Critical elements of a high-capacity fuel cell using an electrolyte paste consisting of fine-grain solid MgO and molten electrolyte for optimum performance.

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