How to Understand Serial Dilutions
A serial dilution is a laboratory technique for controlling the concentration of a chemical or living cells in a liquid. Serial dilutions are stepwise dilutions where an original concentration is diluted by a fixed amount, usually a factor of ten, and the subsequent solution is diluted again by the same factor. Serial dilutions produce a final solution that is a hundredth, a thousandth, a millionth or some other decimal fraction of the original solution. You can understand serial solutions by creating your own serial dilution experiment, as well as by reading about the process or watching a video of one taking place.
Other People Are Reading
Instructions
-
-
1
Create an initial solution of a cupful of water and sugar or salt. The exact amounts are not important, but use a lot of sugar and salt to create a heavy concentration. You can also add food coloring to create a visual indicator of subsequent dilutions.
-
2
Take one ounce of your solution and mix it with nine ounces of water. The concentration is now one-tenth the original. Compare the taste of the original solution and your diluted solution and observe the difference in color.
-
-
3
Repeat this procedure as many times as you'd like. Each dilution will be one-tenth of the previous concentration. After six dilutions, your solution will have one-millionth the concentration of the original solution.
-
1
Tips & Warnings
Read about serial dilutions at the National Health Museum site or in textbooks such as Swamy's Laboratory Manual on Biotechnology. Watch online videos that demonstrate how serial dilutions are performed at sites such as Wellesley College's Biology Concepts or at SciVee.
References
- Photo Credit laboratory image by Oleg Verbitsky from Fotolia.com
