A dilution represents the ratio of the concentrated/ stock solution to the total final volume /weight of both the solute and solvent. Serial dilutions involve the use of a series of dilutions to arrive at the desired concentration instead of making one large dilution as with simple dilution. You begin with a solution lets call it solution A, which has a known volume and then solute will be taken from this and diluted with a solvent forming solution B. Solute will then be taken from solution B and diluted with a solvent to form solution C. Similar steps can be followed until you get the desired final volume. Serial dilutions allows the use of small quantities of solute/solvent to get dilutions which are relatively large. Before you carry out a serial dilution in the lab you will need to know:
*The concentration of the original, stock solution
*The desired concentration of your dilute solution
*The dilution factor and the number of dilution to be made to get the desired concentration
Lets first have a quick review of dilution factors:
A 1:10 dilution represents 1 unit volume of solute is dissolved in 9 unit volumes of solute to get a total solution volume of 10 units.
Take some solute, add solvent from this to make the next dilution. Follow this stepwise arrangement until you have reached your desired concentration .*When carrrying out experiments in the lab be sure to mix your thoroughly
For serial dilutions the following equation applies:
original concentration/New concentration= Overall dilution factor
To get the overall concentration simply multiply all the concentartions
Example:
If a serial dilution consisting of two 1:10 dilutions are carried out, to get the overall dilution factor:
1/10 * 1/10=1/100
