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The value of DeltafG^(Theta) for format...

The value of `Delta_fG^(Theta)` for formation of `Cr_2 O_3` is – 540 kJ `"mol"^(-1)`and that of `Al_2 O_3` is – 827 kJ `"mol"^(-1)` . Is the reduction of `Cr_2 O_3` possible with Al ?

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`Cr_2 O_3 +2 Al to Al_2 O + 2Cr`
` Delta G^@ =- 827 - (-540 ) =- 287 KJ`
For the reduction of `Cr_2 O_3 `with `AI, Delta G^@` is negative. So reduction of `Cr_2 O_3` with aluminium is possible.
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