Use the scratchpad to check your plans, and if you get completely lost, click the ?! button for a workable dilution scheme. In lab, you will often be given a stock solution which you will need to dilute to a given concentration for use in a lab exercise. In the examples in the applet below, the numbers always come out evenly if you choose dilutions of 1/2, 1/5 or 1/10, or their multiples. So put 21.3oz of chemical in the container and fill the rest with water totaling 128oz to make a gallon of solution at a 5:1 dilution. (ii) water required to make 1.5 litres of 10 solution from 100 Stock Strength. Then we take 128oz and divide that by 6 and we get 21.3333333.
HOW TO DO DILUTION SERIES MATH SERIAL
As any measurement or mixing errors are compounded when preparing a series of dilutions (or serial dilutions) it is generally advisable to minimize the number of steps. To make a 5:1dilution ratio for a gallon, we add the ratio numbers together like this: 5+16. There is usually more than one way to achieve the same total dilution, and in deciding the best one to choose, you should avoid using volumes that are really large (this is wasteful and mixing may be a problem) or very small (sample taken may not be representative of the original sample). The trickier part is figuring out a series of dilutions that will achieve this overall dilution. Write n1arn1 n 1 a r n 1 as a series that starts at n 0 n 0. Example 1 Perform the following index shifts. For example, if you want coffee with 5 caffeine molecules per cup, but you have coffee with 5000 molecules per cup, you have to prepare a dilution of 5/5000 or 1/1000. Let’s do a couple of examples using this shorthand method for doing index shifts. In this case, just take the concentration you want to achieve, and divide it by the concentration you currently have. To do this, you need to figure out the overall dilution you’re aiming for. For example: 1/ 3, 1/9, 1/27, 1/81 Notice that each dilution is three - fold relative to the previous one. So let’s put some of these skills together to design dilution schemes. Since the dilution-fold is the same in each step, the dilutions are a geometric series (constant ratio between any adjacent dilutions).