Beer's Law Lab: free chemistry simulation
Shine light through a coloured solution: absorbance depends on concentration, path length and wavelength.
▶ Open the simulationFree, no sign-up. Works on phones, tablets and laptops.
The science
A coloured solution absorbs some of the light that passes through it. The absorbance is proportional to the concentration and to the distance the light travels through the solution. That is how a spectrophotometer measures concentration.
A = ε l c
Things to try
- Double the concentration and check the absorbance doubles.
- Use a wider cuvette and watch absorbance rise.
- Change the wavelength to find where the solution absorbs most.
Topics covered
absorbance transmittance concentration spectrophotometer wavelength
How to use it
Open the simulation, then change the experiment live with the sliders, checkboxes and buttons in the side panel. Drag objects on screen where it makes sense, and use Pause, Step, Speed and Reset in the bottom bar to study every moment.
Frequently asked questions
What does the Beer's Law Lab simulation show?
A coloured solution absorbs some of the light that passes through it. The absorbance is proportional to the concentration and to the distance the light travels through the solution. That is how a spectrophotometer measures concentration.
What is the key equation?
A = ε l c
Is the Beer's Law Lab simulation free?
Yes. It runs free in any web browser on phones, tablets and laptops, with no sign-up or download.
More chemistry simulations
Gas Properties
Pump particles into a box, heat it and change its volume. Ideal gas law and speed distribution.
States of Matter
Heat and cool atoms bound by intermolecular forces: watch solid, liquid and gas form.
pH Scale
Test everyday liquids, dilute them with water, and see how H₃O⁺ and OH⁻ change.
Build an Atom
Add protons, neutrons and electrons. Find the element, its charge and mass number, and whether it is stable.