Why does it not take place at room temperature?

cbse
isolationofelements

#1

The reaction, $Cr_{2}O_{3}$ (s) + 2Al(s)----------> $Al_{2}O_{3}$ + 2Cr;
$\Delta $G° = - 421 kJ
is thermodynamically feasible as is apparent from the Gibbs energy value. Why does it not take place at room temperature?


#2

The reactants are solids, so they cannot react in the present .state or at room temperature. When the temperature is elevated, reactants melt and the reaction proceeds. Therefore, a higher temperature is required.