Concepts

Dilution

One method in which the concentration of a solution can be diluted is by adding more and more water sources (solute free) to the original solution. Using this method, with each new addition, the total volume increases. (Note: this method was covered in an earlier exercise.)

Instead, suppose that you want to dilute your solution while keeping the total volume of your solution constant. To do this, you might first create a solution from two inputs as before, but then instead of just adding more water sources, you could re-mix the existing solution. That is, if you refill one of your original containers with a sample from container #3, refill your other original container with pure water (solvent) and then recombine them in container #3. Thus with each mixing iteration, the resulting solution would become more and more dilute, but the overall volume would not increase.

The equation for the concentration of your solution after n iterations (C3(n)) below, can be derived from the equations for mixing two sources. Please look at the derivation page before continuing.


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