Consider the reaction $\mathrm{Xf} \quad \mathrm{Y}$ at 300 K . If $\Delta \mathrm{H}^0$ and K are $28.40 \mathrm{~kJ} \mathrm{~mol}^{-1}$ and $1.8 \times 10^{-7}$ at the same temperature, then the magnitude of $\Delta \mathrm{S}^0$ for the reaction in $\mathrm{JK}^{-1} \mathrm{~mol}^{-1}$ is $\_\_\_\_$ . (Nearest integer) (Given: $\mathrm{R}=8.3 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}, \ln 10=2.3, \log 3=0.48, \log 2=0.30$ )