Question

Under isothermal condition, a gas at 300 K expands from 0.1 L to 0.25 L against a constant externalpressureof2bar Theworkdonebythe gas i s : [Given that 1Lbar= 100J)

• A. 25 J
• B. 30 J
• C. - 30J
• D. 5 kJ

Answer 1

Answer: (C)

- 30J

Answer 2

$\therefore \; W_{irr} = - P_{ext } \Delta V$
= - 2 bar $\times$ (0.25 - 0.1) L
= - 2 $\times$ 0.15 L-bar
= - 0.30 L-bar
= - 0.30 $\times$ 100 J
= - 30 J