There are many ways of expressing concentrations and dilution.
Using C1V1 = C2V2
To make a fixed amount of a dilute solution from a stock solution, you can use the formula: C1V1 = C2V2 where:
- V1 = Volume of stock solution needed to make the new solution
- C1 = Concentration of stock solution
- V2 = Final volume of new solution
- C2 = Final concentration of new solution
- Formula: C1V1 = C2V2
Using Dilution Factors
To make a dilute solution without calculating concentrations, you can rely on a derivation of the above formula:
(Final Volume / Solute Volume) = Dilution Factor (can also be used with mass)
This way of expressing a dilution as a ratio of the parts of solute to the total number of parts is common in biology. The dilution factor (DF) can be used alone or as the denominator of the fraction, for example, a DF of 10 means a 1:10 dilution, or 1 part solute + 9 parts diluent, for a total of 10 parts.
Source: http://www.quansysbio.com/support/tech-tips/dilutions/
