Concepts

Mixing Two Sources

Conservation of Mass

Mass and volume are neither created nor destroyed by being moved around. Therefore if a third solution is produced by combining two existing solutions, then the volume and mass of the third solution are found from the masses and volumes in the initial solutions:

m3 = m1 + m2 ,

V3 = V1 + V2 .

Combining Concentrations

The concentration in the third chamber is based upon the masses and volumes in the first two chambers:

Note that the concentration for chamber #3 must be found from the masses and volumes of chambers #1 and #2, not directly from the concentrations in chambers #1 and #2.

This is analogous to averaging velocities by considering the total distance and the total time.


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