Although the reduction of `Cr_(2)O_(3)` with Al is thermodynamically feasible, yet it does not occur at room temperature. Why?

Why is N_(2) , less reactive at room temperature?

The reaction, Cr_(2)O_(3)(s) + 2Al(s) to Al_(2)O_(3) +2 Cr, DeltaG^(@)= -421 KJ is thermodynamically feasible as is apparent from the Gibbs energy value. Why does it not take place at room temperature?

Why does nitrogen exist as a diatomic molecule and is a gas at room temperature ?

H_2O is a liquid while hydrogen sulphide is a gas at room temperature. Give reasons.

Although thermodynamically feasible in practice magnesium metal is not used for the reduction of alumina in the metallurgy of aluminium . why?

Explain why H_2 and O_2 do not combine with each other at room temperture.