Calculate the work energy,w,gained or lost by the system when a gas expands from 20 L to 35 L against a constant external pressure of 2.0 atm.[1 L ∙ atm = 101 J]
A)-5.3 kJ
B)-3.0 kJ
C)+3.0 kJ
D)+5.3 kJ

Question

Quizplus · Accepted Answer

The work done by the system is calculated using the formula w = -PΔV, where P is the external pressure and ΔV is the change in volume. Here, ΔV = 35 L - 20 L = 15 L. So, w = -(2.0 atm)(15 L) = -30 L∙atm. Converting to joules: -30 L∙atm × 101 J/L∙atm = -3030 J = -3.0 kJ. The negative sign indicates work is done by the system, hence energy is lost.

Calculate the Work Energy,w,gained or Lost by the System When