The Percent solutions can be in the form of weight/volume percentage, volume/volume percentage or, weight/weight percentage. In each case, the concentration in percentage is calculated as the fraction of the volume or weight of the solute related to the total volume or weight of the solution. Not only for a solution where concentration needs to be expressed in volume percent (v/v%) when the solute is a liquid, but it is also applicable to the numerator in weight units and the denominator in volume units and called weight/volume percent.
Volume Percent Formula
Volume percent ={ Volume of solute / volume of solution} x 100
Example 1
Determine the volume/volume percent solution made by combining 25 mL of ethanol with enough water to produce 200 mL of the solution.
Solution
Given parameters are
Volume of solute is 25 mL
Volume of the solution is 200 mL
Substitute the values in the given formula,
Volume percent = volume of solute /volume of solution x 100%
= {25 mL / 200 mL }x 100%
Volume percent = 12.5 %
Example 2
A solution is prepared by dissolving 90 mL of hydrogen peroxide in enough water to make 3000 mL of solution. Identify the concentration of the hydrogen peroxide solution.
Solution
The given parameters are
Volume of solute is 90 mL
Volume of solution is 3000 mL
Substitute the values in the given formula,
Volume percent = volume of solute /volume of solution x 100%
= 90 mL/ 3000mL x 100%
Volume percent = 3 %
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