Molarity & Dilution Simulator
Dissolve a solute, see the concentration, and work out how much water to add to dilute it.
About the Molarity & Dilution Simulator
Free molarity and dilution simulator. Choose a solute, change moles and volume, see concentration and mass, and find the water needed to dilute using M1V1 = M2V2. Built for chemistry, the molarity & dilution simulator 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.
Dissolve a solute, see the concentration, and work out how much water to add to dilute it. Use it to explore chemistry ideas at your own pace, then check what you found against the key ideas further down this page.
How to use the Molarity & Dilution Simulator
- Use the controls to change Solute, Your compound: molar mass, Your compound: colour, Amount of solute, Solution volume, and more. The simulation reacts instantly.
- Press "Dilute to target", "+ 0.1 L water" to start, reset or change what is happening.
- 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
- Dissolve 0.5 mol in 0.5 L and read the molarity.
- Dilute to half the concentration and find the water needed.
- Change the solute and compare the mass.
- Set a target concentration and press Dilute.
Key ideas you can learn
- Molarity = moles of solute ÷ litres of solution.
- Mass of solute = moles × molar mass.
- Dilution keeps the moles constant: M1 × V1 = M2 × V2.
Where this is used in the real world
Chemists, nurses and pharmacists dilute stock solutions every day, from lab reagents to medicines and cleaning products. Molarity is the standard way to state a concentration.
Who is this simulation for?
Chemistry students from middle school to university, teachers who need a virtual demonstration, and anyone without access to a lab. It is safe, free and repeatable as many times as you like.
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
How do I dilute a solution to a lower concentration?
Use M1V1 = M2V2. Find the final volume V2 = M1V1 / M2, then subtract V1 to get the volume of water to add.
Does adding water change the number of moles?
No. Adding solvent only changes the volume, so the moles of solute stay the same and the concentration drops.
Is the Molarity & Dilution Simulator 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 Molarity & Dilution Simulator 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.