Chemistry
Dilution relation
Adding solvent leaves the moles of solute unchanged, so the concentration-volume product is conserved.
The Formula
M1 x V1 = M2 x V2
Adding solvent leaves the moles of solute unchanged, so the concentration-volume product is conserved.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| M1 | Molarity before dilution | mol/L | The concentrated stock solution. |
| V1 | Volume before dilution | litres | The aliquot taken from the stock. |
| M2 | Molarity after dilution | mol/L | What you solve for when topping up to a final volume. |
What Each Symbol Means
M1mol/L
Molarity before dilution
The concentrated stock solution.
V1litres
Volume before dilution
The aliquot taken from the stock.
M2mol/L
Molarity after dilution
What you solve for when topping up to a final volume.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate molarity page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate Molarity, filed under Science. Every number the guide produces comes from substituting into this one line.