Learning Hub/Simulation Registry/Physics/HL/Chapter 9

Physics HL

Chapter 9: The Gas Laws

Build gas-law fluency from mole counting and pressure origins to $PV = nRT$, Boltzmann scaling, and the limits of ideal-gas assumptions.

2 simulation entries

Simulation: Particle Count Intuition Builder

Set gas phase and molecule count to connect microscopic population size with amount-of-substance scaling and thermal agitation.

Appears in: 9.1 Moles, Molar Mass, and the Avogadro Constant

Thermal Particle Lab

Microstate viewer (60 particles)

Particle spacing and random-motion speed change with phase and temperature.

Energy partition (relative)

Average kinetic (per mol)3741.30 J/mol
Intermolecular potential depth-4.28 a.u.
Internal-energy index14.92 a.u.

Speed distribution sketch

Shift right and flatten as temperature increases.speed

Mean molecule kinetic

6.213e-21 J

RMS speed index

11.43

Compressibility index

0.20

Phase

LIQUID

Use this model to connect the microscopic picture (particle spacing and random motion) with macroscopic language (temperature, compressibility, and internal energy trends).

Simulation: Pressure from Collisions

Use Boyle-mode piston compression to watch how reduced volume increases collision-driven pressure at fixed amount and temperature.

Appears in: 9.2 Pressure and the Ideal-Gas Model, 9.3 Equation of State and Gas Transformations, 9.4 Boltzmann Equation, RMS Speed, and Internal Energy, 9.5 Real Gases and Model Limitations

Ideal Gas Law Lab

Active law interpretation

General mode lets n, V, and T vary freely so you can inspect full PV = nRT coupling.

Container micro-view (animated gas particles + piston)

Volume: 16.00 LPressure: 199.5 kPaTemperature: 320.0 K

P-V map with isotherms

V (L)P (kPa)

State diagnostics

P

199.5 kPa

1.97 atm

T

320.0 K

46.9 deg C

V

16.00 L

0.0160 m^3

Pressure index13%
Thermal index27%
Volume fraction37%

Microscopic metrics

RMS speed c_rms: 533.9 m s^-1

Mean molecular kinetic energy: 6.627e-21 J

Density estimate: 2.100 kg m^-3

Monatomic internal energy estimate: 4788.9 J

Model validity note

Ideal-model range: this state is in a typical low-density, moderate-temperature regime where PV = nRT is usually reliable.

Try this workflow: hold n fixed, then switch between Boyle/Charles/Gay-Lussac modes and verify each ratio form before returning to full-state PV = nRT checks.