Precipitation Reactions Lab
Mix real quantities of ionic solutions, watch a staged nucleation-and-settling animation, check Q against Ksp, then filter, weigh and calculate percent yield.
About the Precipitation Reactions Lab
Free precipitation reaction lab. Pick two ionic solutions with real concentrations and volumes, mix them and watch the precipitate nucleate and settle, get the net ionic equation and live ion concentrations, compare Q to Ksp, filter and weigh to find percent yield, and try the Unknown Solution challenge. Built for chemistry labs, the precipitation reactions lab runs instantly in your browser: change a setting or drag an object and the result updates at once, so you learn by trying things out rather than only reading about them.
Mix real quantities of ionic solutions, watch a staged nucleation-and-settling animation, check Q against Ksp, then filter, weigh and calculate percent yield. Use it to explore chemistry labs ideas at your own pace, then check what you found against the key ideas further down this page.
How to use the Precipitation Reactions Lab
- Use the controls to change Chemical, Concentration, Volume (pipetted). The simulation reacts instantly.
- Where you see a glowing handle, object, weight or atom, drag it with your mouse or finger. Everything responds in real time.
- Watch the readouts and graphs update as you experiment, and compare what you see with the key ideas below.
Things to try
- Mix silver nitrate with sodium chloride and watch the nucleation animation.
- Try lead(II) nitrate with sodium sulfate.
- Check the Solubility/Ksp tab to see Q compared against Ksp.
- Filter and weigh a precipitate, then calculate your percent yield.
- Try the Unknown Solution challenge.
Key ideas you can learn
- A precipitate forms when two ions combine into an insoluble compound.
- Solubility rules tell you which combinations stay dissolved, and the solubility product Ksp tells you precisely: if Q > Ksp a precipitate is expected.
- The net ionic equation shows only the ions that actually form the solid; the rest are spectator ions.
- Percent yield compares the mass you actually recover after filtering and drying to the mass predicted by stoichiometry.
Where this is used in the real world
Precipitation is used in water treatment, medicine (barium meals), pigments, and analysing which ions are in a sample.
Who is this simulation for?
Students preparing for practical exams and teachers who want a virtual lab. You can repeat the experiment without chemicals, waste or safety risks.
For teachers: project it on the board, let students predict what will happen, then run it together. For students: change one thing at a time and write down what changes.
Frequently asked questions
What is a precipitate?
An insoluble solid that forms when two solutions are mixed. It appears as cloudiness that settles into a solid, driven by nucleation and crystal growth.
What are spectator ions?
Ions that stay dissolved and do not take part in forming the solid. They are left out of the net ionic equation.
What does it mean if Q is bigger than Ksp?
Q is the reaction quotient using the concentrations you actually have. If Q exceeds the solubility product Ksp, the solution is supersaturated and a precipitate forms until Q falls back to Ksp.
Is the Precipitation Reactions Lab free to use?
Yes. It is completely free, with no signup, no download and no ads inside the simulation. It runs in your web browser.
Does the Precipitation Reactions Lab work on a phone or tablet?
Yes. It uses touch as well as the mouse, so you can drag objects with your finger. A larger screen makes the controls easier to see.