Question

For a spontaneous reaction the DeltaG, equilibrium constant(K) will be:

• -ve,>1
• -ve,<1
• +ve,>1
• +ve,<1

Solution

For a spontaneous reaction the change in gibbs free energy is negative.

DeltaG<0

Now we know that DeltaG=DeltaG^@-RTlnK, but when the reaction is in equilibrium DeltaG=0.

So we get that DeltaG^@=-RTlnK. For this question we are assuming that in the standard state the reaction is spontaneous so DeltaG^@<0.

Hence we get that lnK>0=>k>1