Question

Given below are two statements:
Statement I : According to the Ellingham diagram, any metal oxide with higher ΔG° is more stable than the one with lower ΔG°.
Statement II : The metal involved in the formation of oxide placed lower in the Ellingham diagram can reduce the oxide of a metal placed higher in the diagram.
In the light of the above statements, choose the **most appropriate **answer from the options given below

• A. Both Statement I and Statement II are correct.
• B. Both Statement I and Statement II are incorrect.
• C. Statement I is correct but Statement II is incorrect.
• D. Statement I is incorrect but Statement II is correct.

Answer 1

Answer: (D)

Statement I is incorrect but Statement II is correct.

Answer 2

Ellingham diagram is plot of $ΔG$ vs T.
The criterion for the feasibility of a thermal reduction is that at a given temperature Gibbs energy change of a reaction must be negative. The change in Gibbs energy,ΔG for any process at any specified temperature, is given by the equation
$\Delta G = \Delta H - T \Delta S$
where ΔH = enthalpy change and $ΔS$ = entropy change
According to the ellingham diagram, any metal oxide with higher ΔG° has a tendency of getting reduced by the metal whose metal oxide has lower value of ΔG°.
Therefore, Statement I is incorrect but Statement II is correct.