A sample of an ideal gas is expanded to twice its original volume of 1m³ in a reversible process for which P=αv² where α=5 atm/m⁶ . If Cv,m=20 Jmol⁻¹K⁻¹, determine the approximate molar change in entropy for the process.
A. 4 Jmol⁻¹K⁻¹
B. 47.35 Jmol⁻¹ K⁻¹
C. 40 Jmol⁻¹ K⁻¹
D. 4 Jmol⁻¹ K⁻¹.