EXAMPLE Dilution Problem:

What is the molarity of a nitric acid solution made by diluting 25.0 mL of a 15.8 M HNO3 solution to 1.50 L?

Solution:  

We recognize this as a dilution problem because it mentions two concentrations of the same substance and refers to the dilution of a more concentrated solution to form a more dilute solution. We can therefore use the dilution equation.

MC = 15.8 M       VC = 25.0 mL       MD = ?       VD = 1.50 L

MCVC = MDVD   

 
     = 0.263 M HNO3

Notice that a unit conversion is necessary to make our units cancel to yield a molarity unit.  

Alternatively, we could work the problem using the dimensional analysis technique:

                         = 0.263 M HNO3

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