The entropy versus temperature plot for phases $$\alpha$$ and $$\beta$$ at 1 bar pressure is given. $$S_T$$ and $$S_0$$ are entropies of the phases at temperatures T and 0 K, respectively.
The transition temperature for $$\alpha$$ to $$\beta$$ phase change is 600 K and $$C_{P,\beta} - C_{P,\alpha} = 1$$ J mol$$^{-1}$$ K$$^{-1}$$. Assume $$(C_{P,\beta} - C_{P,\alpha})$$ is independent of temperature in the range of 200 to 700 K. $$C_{P,\alpha}$$ and $$C_{P,\beta}$$ are heat capacities of $$\alpha$$ and $$\beta$$ phases, respectively.