Dynamic Equilibrium & Le Chatelier's Principle

R + B ⇌ RB - watch equilibrium establish, then disturb it

Conditions

Temperature25°C
Pressure (volume)1.0×
Initial amount of R150
Initial amount of B150

Perturb the system

Add or remove particles mid-run to see the system respond (Le Chatelier). Adding R/B pushes the forward reaction; adding RB pushes the reverse.
R amount50
B amount50
RB amount50
Time elapsed0.0 s
● R0
● B0
● RB0
Forward rate0 /s
Reverse rate0 /s
Not at equilibrium
All reactantsAll product
0
R
0
B
0
RB

Energy profile

Rate vs. time

Forward (orange) and reverse (blue) reaction events per second. At dynamic equilibrium both continue - but at equal rates.

Boltzmann distribution - forward (R+B colliding)

Same particle energies as the panel on the right - this is one gas at one temperature, not two. Red marks Ea(fwd): the energy an R–B collision needs to react. The shaded tail grows as temperature rises; only a catalyst moves the line itself.

Boltzmann distribution - reverse (RB breaking apart)

Purple marks Ea(rev): the energy an RB needs to break back apart. It's higher than Ea(fwd) by a fixed amount (ΔH) - because the reaction is exothermic, not because RB particles are somehow different from R+B pairs. That's why only a small sliver clears it: fewer successful "attempts" per particle, balanced at equilibrium by there being more RB particles making them.
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