Extraction of Metals - Result Question 16
####16. The correct statement regarding the given Ellingham diagram is
(2019 Main, 9 Jan II)
(a) At $800^{\circ} C, Cu$ can be used for the extraction of $Zn$ from $ZnO$
(b) At $1400^{\circ} C, Al$ can be used for the extraction of $Zn$ from $ZnO$
(c) At $500^{\circ} C$, coke can be used for the extraction of $Zn$ from $ZnO$
(d) Coke cannot be used for the extraction of $Cu$ from $Cu _2 O$
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Solution:
- From the Ellingham diagram, we can say that any oxide with lower value of $\Delta G^{\circ}$ is more stable than a oxide with higher value of $\Delta G^{\circ}$. We can also predict that the oxide placed higher in the diagram can be reduced by the element involved in the formation of its oxide placed lower at that temperature in the diagram.
It is happening in case of $ZnO$ for its reduction by $Al$ at $1400^{\circ} C$.