X(-56 x 4.184) = -117 kJ/mole AGYo = ><(-88 x 4.184) = -184 kJ/mole

The factor of V2 accounts for the fact that the Ellingham diagram gives free energies of formation per mole of O2 while reactions (10.2a) and (10.2b) are written for one mole of oxide. Combining the above values gives AGĀ° = AGyo" AGXo = "67 kJ/mole, and Eq (10.5b) with z = 2 gives a cell EMF of:

The couples in the half-cells are not restricted to metals and their oxides. Problem 10.7 analyzes a cell in which one electrode contains two oxides of the same metal. However, all components of the cell are pure, and are thus in standard states. Nonstandard variants of the solid-state electrochemical cell are presented in the following section.


Reactions (10.2) suggest an alternate interpretation of the electrochemical cell based on Reaction (10.1). Each half cell of Eq (10.4) is a MO/M couple with a characteristic oxygen pressure (po2 )MO)/m (see

Digression 2 in Sect. 9.9.1). The electrochemical cell of Equation (10.4) could equally well be written as:

(O2)xo/x ||electrolyte||(O2)yo/y In place of reactions (10.3), the half-cell reactions are:

Instead of Equation (10.5b), the cell EMF is:

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Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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