Solution Preparation Calculator

n = c × V, m = n × M

Calculate the mass of solid needed to prepare a solution at a target molar concentration and final volume.

Inputs

Substance (optional)

Molecular weight

g/mol

Desired concentration

Final volume

Output mass unit

Result

0.5844 g

Weigh out this mass and dissolve to a final volume of 100 mL.

Calculation

Amount of substance
n = c × V
n = 0.1 mol/L × 0.1 L
n = 0.01 mol
Required mass
m = n × M
m = 0.01 mol × 58.44 g/mol
m = 0.5844 g

Inputs

Molecular weight: 58.44 g/mol
Target concentration: 0.1 mol/L
Final volume: 100 mL

Dissolve the solid in less than the final volume, then make up to the final volume.

At the bench

1 · Weigh out
0.5844 g
Solid on a tared balance
2 · Dissolve
~70 mL
Add part of the solvent and stir until fully dissolved
3 · Make up to volume
100 mL
Fill to the mark, then invert to mix
4 · Final solution
0.100 mol/L
Label with substance, concentration and date

Volumes for the dissolving step are indicative — always make up to the final volume mark.

About this calculator

To prepare a solution of a known molar concentration, first calculate the amount of substance required from the concentration and the final volume (n = c × V), then convert that amount into a mass using the molecular weight (m = n × M).

Values are converted to mol/L and litres internally, so any combination of the supported units gives the same answer. Dissolve the weighed solid in a smaller volume of solvent first and then make up to the final volume — the volume of the dissolved solid is included in the final volume.

Example: 100 mL of a 0.100 mol/L NaCl solution (M = 58.44 g/mol) requires 0.5844 g NaCl.

LabReadyTools is provided as a calculation aid. Users remain responsible for verifying calculations, units, chemical compatibility, experimental procedures and applicable safety requirements before laboratory use.