High school10 min

Molar concentration and preparing a solution from a solid

C = n/V without picking the wrong volume, the mass to weigh for a volumetric flask, and going from a label's g/L or % to mol/L.

The essentials

1

Molar concentration

C=nVC = \frac{n}{V} with nn in mol and VV in litres: CC is in mol/L\text{mol/L} (also written "1 M1\ \text{M}" for 1 mol/L1\ \text{mol/L}). VV is the volume of the solution, not of the water added. The other way round: n=C×Vn = C \times V.
2

The mass to weigh

Members only

3

Mass concentration

Members only

4

Mass fraction of a commercial solution

Members only

5

Taking a sample does not change the concentration

Members only

ƒWrite my own sheetOr start from a blank page: rewriting a concept in your own words is how it sticks.