Ncert Exercises & Solutions

Which quantity out of $∆_{r} G$ and $∆_{r} G^{⊝}$ will be zero at equilibrium?

Gibbs energy for a reaction in which all reactants and products are in standard state.

∆_{r} G^{⊝}

is related to the equilibrium constant of the reaction as follows

∆_{r} G = ∆_{r} G^{⊝} + RT In K

At equilibrium,

0 = ∆_{r} G^{⊝} + RT In K (∴ ∆_{r} G = 0)

∆_{r} G^{⊝} = - RT In K

∆_{r} G^{⊝} = 0

when K=1

For all other values of K.

∆_{r} G^{⊝}

will be non-zero.