Pro 🔒~25 min

Gas Properties

Pressure, volume, temperature, and the ideal gas law

How it works

The ideal gas law PV = nRT relates pressure, volume, amount, and temperature of a gas. At the molecular level, pressure arises from particles colliding with container walls. Temperature is proportional to average kinetic energy. Boyle's Law (P ∝ 1/V at constant T,n) can be observed by changing volume. Charles's Law (V ∝ T at constant P,n) relates volume to temperature. Gay-Lussac's Law (P ∝ T at constant V,n) shows pressure increases with temperature. Deviations from ideal behavior occur at high pressure (small volume) or low temperature, where intermolecular forces become significant.

Upgrade to Pro to access this experiment

Step-by-step

  1. Use the sliders to adjust temperature, container volume, and number of gas particles.
  2. Watch particles bounce around — faster at higher temperatures, more wall collisions in smaller volumes.
  3. The real-time graph plots pressure data so you can verify gas law relationships.

Key formulas

  • PV=nRTPV = nRTIdeal Gas Law: P = pressure (atm), V = volume (L), n = moles, R = 0.08206 L·atm/(mol·K), T = temperature (K)
  • KEavg=32kBTKE_{\text{avg}} = \frac{3}{2} k_B TAverage kinetic energy per particle is proportional to temperature. k_B = 1.38 × 10⁻²³ J/K

Frequently asked questions

If you halve the volume at constant T and n, what happens to pressure?
Boyle's Law: P₁V₁ = P₂V₂ → pressure doubles.
At 300 K, 1 mol of gas in 10 L: what is the pressure?
P = nRT/V = (1)(0.08206)(300)/10 = 2.46 atm.
Why do real gases deviate from PV=nRT at very high pressures?
At high P, particle volume is not negligible and intermolecular forces matter (van der Waals corrections).