For each process, we can use the ideal gas law and the first law of thermodynamics to calculate the values of W, Q, ΔU, and ΔH.

(1) Free expansion process: In a free expansion process, the gas expands into a vacuum, so no work is done on or by the system. Therefore, W = 0.

Since the process is adiabatic (no heat transfer), Q = 0.

From the first law of thermodynamics, ΔU = Q - W = 0 - 0 = 0.

Since the process is adiabatic, ΔH = ΔU = 0.

(2) Expands against constant external pressure p_su = 100000 Pa: The work done in this process can be calculated using the formula: W = -pΔV, where p is the external pressure and ΔV is the change in volume.

Since the pressure is constant, we can use the ideal gas law to calculate the change in volume: ΔV = V2 - V1 = nRT2/p2 - nRT1/p1

Substituting the given values: ΔV = 10 mol * 8.314 J/(molK) * (25 + 273.15 K) / 100000 Pa - 10 mol * 8.314 J/(molK) * (25 + 273.15 K) / 10000000 Pa

Calculating ΔV: ΔV = 0.025 m^3 - 0.0025 m^3 = 0.0225 m^3

Calculating the work done: W = -pΔV = -100000 Pa * 0.0225 m^3 = -2250 J

Since the process is adiabatic (no heat transfer), Q = 0.

From the first law of thermodynamics, ΔU = Q - W = 0 - (-2250 J) = 2250 J.

Since there is no change in pressure, ΔH = ΔU = 2250 J.

(3) Expands isothermally and reversibly: In an isothermal process, the temperature remains constant. Therefore, ΔU = 0.

From the first law of thermodynamics, Q = W.

Since the process is reversible, we can use the formula for work done in an isothermal process: W = -nRTln(V2/V1)

Substituting the given values: W = -10 mol * 8.314 J/(mol*K) * (25 + 273.15 K) * ln((25 + 273.15 K) / (25 + 273.15 K))

Calculating W: W = 0 J

Since Q = W and no work is done, Q = 0.

Since ΔU = 0 and the process is isothermal, ΔH = 0.

To summarize: (1) Free expansion process: W = 0, Q = 0, ΔU = 0, ΔH = 0. (2) Expands against constant external pressure p_su = 100000 Pa: W = -2250 J, Q = 0, ΔU = 2250 J, ΔH = 2250 J. (3) Expands isothermally and reversibly: W = 0 J, Q = 0, ΔU = 0, ΔH = 0.

Thermodynamic Processes of Ideal Gas Expansion: Work, Heat, Internal Energy and Enthalpy Changes

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