An Ellingham diagram provides information about:
(1) the kinetics of the reduction process.
(2) the conditions of pH and potential under which a species is thermodynamically stable.
(3) the pressure dependence of the standard electrode potentials of reduction reactions involved in the extraction of metals.
(4) the temperature dependence of the standard Gibbs energies of formation of some metal oxides.
(4) the temperature dependence of the standard Gibbs energies of formation of some metal oxides.
Explanation:
Ellingham diagram is graph of ΔGº vs T of any metal / element oxide. Since
ΔGº = ΔHº - TΔSº
for most metal oxide formation
metal (s) + oxygen (g) → metal oxide (s)
ΔHº = - ve
ΔSº = -ve
so graph will be a straight line with – ve y- intracept & +ve slope.