COLLISION THEORY

COLLISIONS / s0

EFFECTIVE / s0

EFFECTIVE SHARE0%

REACTIONS0

MODE1 2

PRESETS3 4 5 6

NEXT COLLISIONA E O L B

CONDITIONS↑ ↓

Temperature400 K

Temperature600 K

Concentration50 A–B + 50 C

Concentration80 A–B + 80 C

CatalystOff On

GRAPHSM

PLAYBACKSPACE S R

ENERGY DISTRIBUTION

ENERGY PROFILE

REACTANTS LEFT

Effective ~~E_aE_a′~~

Interface hidden · press / to show

KEYS & MODEL

KEYS

1 / 2: Slow-mo / Live
3 4 5 6: Presets: Start, Hot, More particles, Catalyst (Live)
Space: Pause · next collision in Slow-mo
S: Speed 1× / ½× / ¼× (Live)
R: Reset
↑ ↓ ← →: Temperature
K: Catalyst
C: Compare (Live)
A E O L B: Next collision type (Slow-mo)
M: Graphs on / off
H: Hide controls
/: Hide the whole interface
F: Full screen
?: This panel
Esc: Close this panel · show the interface

MODEL

Schematic model: A–B + C → A + B–C. Energies are in arbitrary units.
Effective collision: C hits the B end of A–B, and the energy along the line of centres is at least E_a.
Catalyst: an alternative pathway with a lower activation energy, E_a′ = 0.6 E_a. ΔH is unchanged.
Higher concentration: more particles in the same box, so more collisions per second. The shape of the energy distribution does not change; it depends on temperature only.
Walls exchange heat with the surroundings, so the box keeps a Maxwell–Boltzmann distribution. New products take the box temperature at once.
No reverse reaction is modelled.