When compared to $\Delta G^\circ$ for the formation of $Al_2O_3$, the $\Delta G^\circ$ for the formation of $Cr_2O_3$ is
- higher
- lower
- same
- unpredicted
The Correct Option is A
Solution and Explanation
Hence,$ \Delta G?$ of $ Cr_2O_3$ > $\Delta G?$ of $ Al_2O_3$
Top Questions on General Principles and Processes of Isolation of Elements
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The reaction that does NOT take place in a blast furnace between 900 K to 1500 K temperature range during extraction of iron is?
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- Which of the following ore is not in oxide form?
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Concepts Used:
General Principles and Processes of Isolation of Elements
What are Ores and Minerals?
Minerals are the naturally occurring, homogeneous inorganic solid substances. They are having a definite chemical composition and crystalline structure, hardness and color. For example, copper pyrite, calamine, etc.
Impurities in an ore are called gauge. The removal of a gauge from the ore is called concentration ore.
Several steps are involved in the extraction of pure metal from ores. Major steps are as follows –
- Concentration of the ore
- Isolation of the metal from its concentrated ore
- Purification of the metal