Question

A protein undergoes reversible thermal denaturation from its initial state $\mathbf{N}$ to denatured state $\mathbf{D}$ according to $\mathbf{N} \rightleftharpoons \mathbf{D}$. At $60^{\circ}C$, the concentrations of both $\mathbf{N}$ and $\mathbf{D}$ are equal at equilibrium, and the standard enthalpy change of denaturation is $666\text{ }kJ{\text{ }mol}^{- 1}$. The standard entropy change ( $\Delta S^{\circ}$ in $kJK^{- 1}{\text{ }mol}^{- 1}$ ) of the protein upon denaturation at 60°C is closest to