Chemistry Question 74 – NEET-UG 2026

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