Chemistry I / The First Law of Thermodynamics
Practice question · Numerical answer

A gas expands from 1.0 L to 4.0 L against a constant external pressure of 3.0 atm. Compute the work done on the gas, in L atm.

Hints
  1. Use w = -P times the change in volume.
  2. Compute -3.0 x (4.0 - 1.0).
Show the answer

-9 (answers within ±0.1 count)

Why

w=PΔV=3.0×3.0=9.0w = -P\Delta V = -3.0 \times 3.0 = -9.0 L atm. The gas does work on its surroundings, so from the system’s point of view the value is negative.

Read the lesson: The First Law of Thermodynamics →

Practise The First Law of Thermodynamics

The app has 4 more questions on this lesson, and keeps your place in the course. Chemistry I is free to start.

More questions on The First Law of Thermodynamics