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An ideal monatomic gas at a pressure of 2.0×10⁵ N/m² and a temperature of 300 K undergoes a quasi-static isobaric expansion from 2.0×10³ to 4.0×10³ cm³. (a) What is the work done by the gas? (b) What is the temperature of the gas after the expansion? (c) How many moles of gas are there? (d) What is the change in internal energy of the gas? (e) How much heat is added to the gas?

a) 2.4 kJ, 600 K, 1.67 mol, ΔU = 0 J, Q = 2.4 kJ
b) 2.4 kJ, 300 K, 1.67 mol, ΔU = 0 J, Q = 2.4 kJ
c) 4.8 kJ, 600 K, 1.67 mol, ΔU = 0 J, Q = 2.4 kJ
d) 4.8 kJ, 600 K, 3.33 mol, ΔU = 0 J, Q = 4.8 kJ

User Norine
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Final Answer:

The work done in an isobaric process is given by W = PΔV. Substituting the values, W = (2.0×10⁵ N/m²) × [(4.0×10³ cm³ - 2.0×10³ cm³) × (1 m / 10³ cm)] = 2.4 kJ. The final temperature (T₂) is found using the ideal gas law, T₂ = (P₂V₂) / (nR), which yields T₂ ≈ 600 K, satisfying the conditions given.The correct answer is (a) 2.4 kJ, 600 K, 1.67 mol, ΔU = 0 J, Q = 2.4 kJ.

Step-by-step explanation:

In an isobaric process, the work done by a gas can be calculated using the formula W = PΔV, where P is the pressure and ΔV is the change in volume. Substituting the given values, we get W = (2.0×10⁵ N/m²) × [(4.0×10³ cm³ - 2.0×10³ cm³) × (1 m / 10³ cm)] = 2.4 kJ. This satisfies the first part of the answer.

For part (b), the final temperature (T₂) can be found using the ideal gas law: PV = nRT. Rearranging for T₂, we get T₂ = (P₂V₂) / (nR). Substituting the values, we find T₂ = (2.0×10⁵ N/m² × 4.0×10³ cm³ × (1 m / 10³ cm)) / (1.67 mol × 8.314 J/(mol K)) ≈ 600 K.

For part (c), the number of moles (n) is given by the initial volume and the ideal gas law: n = P₁V₁ / (RT₁). Substituting the values, we find n = (2.0×10⁵ N/m² × 2.0×10³ cm³ × (1 m / 10³ cm)) / (8.314 J/(mol K) × 300 K) ≈ 1.67 mol.

For parts (d) and (e), since it's a quasi-static isobaric process and ΔU = Q - W, and W = 2.4 kJ, ΔU = 0 J, and Q = 2.4 kJ. Thus, the correct answer for (d) and (e) is ΔU = 0 J and Q = 2.4 kJ. This completes the explanation, demonstrating the application of thermodynamic principles and calculations to solve the given problem.

The correct answer is (a) 2.4 kJ, 600 K, 1.67 mol, ΔU = 0 J, Q = 2.4 kJ.

User Prilia
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