NTA Abhyas JEE Main2020ChemistryThermodynamics (C)Practice
Two moles of an ideal gas is expanded isothermally and reversibly from 1 litre to 10 litre at 300 K. The enthalpy change (in kJ) for the process is
Options
- A11.4 kJ
- B-11.4 kJ
- C0 kJ
- D4.8 kJ
Correct answer
C. 0 kJ
Step-by-step solution
Δ H = Δ E + P V = Δ E + Δ RT = Δ E + R Δ T For isothermal expansion of ideal gas, Δ E = 0 Δ E = C v Δ T So Δ H = 0 + 0 = 0 Δ T = 0 putting Δ E = C v Δ T , Δ H = C v Δ T + R Δ T = C v + R Δ T = C p Δ T for 1 mole for n moles, Δ H = nCp Δ T = 0