Is this correct?

Question

HEX₃(aq) + H₂O(l) ⇌ H₃O⁺(aq) + EX₃⁻(aq)

∆G^o = +47 kJ/mol_rxn

The reaction between the acid HEX₃(aq) and water is shown above. Based on the chemical equation and the value of ∆G^o given above, which of the following gives the relative size of Ka and pH of a 0.10 M solution of HEX₃(aq)?

1. Ka = 1 and pH < 1

1. Ka << 1 and pH = 1

1. Ka > 1 and pH > 1

1. Ka << 1 and pH > 1

Answer 1

∆G = -RT ln K

A positive value of ∆G tells us that the reaction is not spontaneous (favorable) and that K <1.

So, your answer appears to be the correct one. Ka <<1 and pH > 1