Mass Percentage (%w/w) - The number of mass parts of a solute that is present in 100 mass parts of solution is called Mass Percentage Of Solution.
Or The number in grams of solute present in 100 grams of a solution is called the Mass Percentage (%w/w) of that Solution.
%w/w = [Mass of solute (in grams)/Mass of solution (in grams)] × 100
Or %w/w = [{Mass of solute (in grams)}/{mass of solute + mass of solvent}] x 100
Generally solute is represented by A and solvent is represented by B.
Concentration expressed in Mass Percentage is commonly used to express the concentration of solutions of commercial chemical substances used in chemical industries.
For example, the commercial bleaching solution contains sodium hypo chloride 3.62%w/w.
Similarly, commercial H₂SO₄ is 95.8%w/w.
Their values decrease with increasing temperature.