Question

For irreversible expansion of an ideal gas under isothermal condition, the correct option is :

(1) ΔU = 0, ΔS_total = 0

(2) ΔU ≠ 0, ΔS_total ≠ 0

(3) ΔU = 0, ΔS_total ≠ 0

(4) ΔU ≠ 0, ΔS_total = 0

Answer 1

Correct answer is (3).

For irreversible expansion of an ideal gas under isothermal condition

ΔU = 0, ΔS_total ≠ 0