Solution Preparation Calculator

Work out solution preparation instantly with clear inputs, formula shown and shareable results.

About Solution Preparation Calculator

Preparing a solution of known molarity is a two-step weighing calculation: moles = molarity x volume in litres, then mass = moles x molar mass. For 500 mL of 0.25 M sodium chloride that is 0.125 mol, or 7.305 g of NaCl dissolved and made up to the mark.

Formulas

Moles required

moles = molarity x volume (L)

Mass to weigh

mass (g) = moles x molar mass

Worked example

With the default values below, Solution Preparation Calculator returns Solute To Weigh Out of 7.3050. Change any input above and every figure here is recalculated in your browser.

Inputs used

Target molarityminimum 0 M: 0.25 M
Final volumeminimum 0.01 mL: 500 mL
Molar mass of soluteminimum 0 g/mol: 58.44 g/mol

Results

Solute To Weigh Out: 7.3050 g
Moles Required: 0.125000
Same Mass In Milligrams: 7,305.00
Strength: 14.6100 g/L

Step by step

1Values used
2Moles required
3Mass to weigh
4Solute To Weigh Out= 7.3050 g
5Moles Required= 0.125000
6Same Mass In Milligrams= 7,305.00
7Strength= 14.6100 g/L

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 6 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Should I add the solute to the full volume of water?

No. Dissolve in less solvent than the target volume, then make up to the graduation mark, because dissolving changes the volume.

What if my balance reads milligrams?

The same mass is shown in milligrams as well, which is easier for sub-gram quantities.