1) Consider a system consisting of 1.5 mol CO2 (g), initially at 15°C and 9.0 atm and confined to a cylinder of cross-section 100.0 cm2 , The sample is allowed to expand adiabatically against an external pressure of 1.5 atm until the piston has moved outwards through 15 cm. Assume that carbon dioxide may be considered a perfect gas with CV,m = 28.8 J K-l mol-1 , and calculate; (a) q, (b) w, (c) ∆U, (d) ∆T, (e) ∆S.

Initially at 300 K and 10 atm pressure, 1 mol of a gas is allowed to expand adiabatically against a constant pressure of 4 atm until equilibrium is achieved. Assume the gas to be ideal with Cp,m = 28.58 + 1.76 x 10^-2 T(The units of T are K and the units of Cp,m are J K-1 mol-1.) Compute DU, DH, q and w.

(a) Suppose that attractions are the dominant interaction between gas molecules, and the equation of state is p = nRT/V – n2a/V2. Determine the work (W(non-ideal gas)) of reversible, isothermal expansion of such a gas from initial volume V (initial) = 20.0 L to final volume V(final) = 40.0 L if n = 2.00 mol, T = 300 K, and a = 3.621 atm-L2/mol2. Watch your units.  (b)Determine the work (W(ideal gas) of reversible, isothermal expansion of an ideal gas from initial volume V (initial) = 20.0 L to final volume V(final) = 40.0 L if n = 2.00 mol and T = 300 K.  (c) Show the difference W(non-ideal) – W(ideal). If all your calculations are done correctly, this result shows you the effect of attractive interaction between gas particles on the work done by the system.

Assuming ideal gas behavior, calculate ΔH Assuming ideal gas behavior, calculate q Assuming ideal gas behavior, calculate ΔU w =−2.48×104 J

At 100°C, the standard molar is the enthalpy of vaporization  ∆vapH⊖m  of water 40.7 kJ mol-1 while the standard molar entropy of vaporization ∆vapS⊖m = 109.1 J mol-1 K-1. The molar standard heat capacities of water as a liquid and water as a gas are, respectively, 75,291J mol-1 K-1 and 33.58 J mol-1 K-1. 6) Calculate both the standard molar enthalpy of vaporization and the standard molar entropy of vaporization at 25°C. It must be assumed that the heat capacities are independent of the temperature.