Ellingham diagram depicts the relation between temperature and the stability of a compound. At higher temperatures, some compounds witness drastic changes in their properties. The diagram is basically a graphic representation of Gibbs Free Energy and its flow. We use Ellingham diagram to formulate reduction equations and to find out the most suitable reducing agents inorder to reduce oxides to obtain pure metals. 

The Graph is plotted between change in Gibbs free enery and temperature. The slope of the curve denotes Entropy and the intercept denotes Enthalpy. Enthalpy change is not dependent upon temperature.

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