Molarity helps obtain the solvent

Running head: AP CHEMISTRY 1
Ap Chemistry
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AP CHEMISTRY 2
Molarity vs Parts per Million
The two methods; molarity and parts per million are used to measure the concentration of
a solution. Molarity refers to the number of solute moles in every liter of solution. It is calculated
as follows;
Molarity= moles of solute
liters of solution
Parts per million is defined as the solute mass in a million sample of the amount of solution. It is
derived as shown below;
parts per million= mass of solute
liters of solution∗1000000
Molarity is the main unit of determining solution concentration. It is used to calculate the number
of moles in every liter of the solution. Molarity helps obtain the solvent volume or quantity of
solute. Parts per million is mostly applied in determining the concentration of contaminants in
water, soil, and sediments (Savva, 2019).
Both molarity and parts per million rely on the weight of a molecule of a substance, that
is, g/mol. The two measures of concentration differ in the sense that molarity determines the
number of moles per liter while parts per million calculate the mass per liter (Harris, 2011).
Molarity is the most beneficial to use since it helps in comparing different substances on a
molecular basis. For instance, comparing for potency in a bioassay. For as long as the substance
being measured can be classified in molecular form, it becomes more easy and common to use
molarity as the measure of the concentration. It is easy to compare solvents based on their
molecular concentration. The use of parts per million fails to allow comparison of substances
based on their molecules. Otherwise, ppm is much helpful whenever the substance under
measurement does not have an established and defined molecular weight, for example, extracts