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MHT CET202620 April 2026Morning ShiftChemistryThermodynamics (C)Actual

If 2 mole of an ideal gas expand isothermally and reversibly at 27^ C from 1 dm ^3 to 1 m ^3 calculate work done? [R = 8.314 J K ⁻¹ mol ⁻¹]

Options

  1. A-49.95 kJ
  2. B-99.90 kJ
  3. C-34.46 kJ
  4. D-68.92 kJ

Correct answer

C. -34.46 kJ

Step-by-step solution

Given: n = 2 mol T = 27^ C = 300 K V₁ = 1 dm ^3 V₂ = 1 m ^3 = 1000 dm ^3 R = 8.314 J K ⁻¹ mol ⁻¹ The work done in a reversible isothermal expansion is given by: W = -2.303 nRT ₁₀ ( V₂ V₁ ) Substituting the given values: W = -2.303 2 8.314 300 ₁₀ ( 1000 1 ) W = -2.303 600 8.314 3 W = -34464.8 J W = -34.46 kJ Answer: -34.46 kJ

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