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The reaction Cr2O3+2AltoAl2O3+2Cr (tri...

The reaction
`Cr_2O_3+2AltoAl_2O_3+2Cr` `(triangleG^(ɵ)=-421kJ))`
Is thermodynamically feasible as is apparent from the Gibbs energy value. Why does it not take place at room temperature?

A

Certain amount of activation energy is essential for thermodynamically feasible reactions also.

B

Due to high melting point of chromium oxide the reaction does not take place.

C

Overall value of `DeltaG` for the net reaction becomes positive.

D

Molecules of `Cr_(2)O_(3)` and Al are not oriented properly.

Text Solution

Verified by Experts

The correct Answer is:
A
The spontaneous reaction also requires a certain amount of activation energy therefore heating is required.
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NCERT FINGERTIPS ENGLISH-GENERAL PRINCIPLES AND PROCESSES OF ISOLATION OF ELEMENTS-Assertion And Reason
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