19. Consider a container with a piston containing 2.0 moles of a monatomic ideal gaswith initial conditions of V = 6.0 L and P = 2.0 atm at 300 K. If the externalpressure suddenly increases to 4.0 atm and the gas is compressed isothermally,which of the following statements about this process is true? (gas constant R = 8.314 J·K-1 mol -l；In2 =0.693)
(A)This is a reversible process.
(B)This process is spontaneous.
(C)The change of enthalpy (△H) is positive.
(D)The entropy change (△S) is -11.5 J/K.
(E)The entropy change of the surrounding (△Ssurr) is -4.1 J/K.