w/v
an abbreviation for "weight by volume" which describes the concentration of a substance in a solution or mixture. The weight by volume is the mass (in grams) of the substance dissolved in 100 milliliters of solution.
For example, the concentration of fluoride in toothpaste is usually about 0.15% w/v, meaning that there is 0.15 gram of fluoride per 100 milliliters of toothpaste.
w/w
an abbreviation for "by weight" which describes the concentration of a substance in a solution or mixture.
For example, 2% w/w means that the mass of the substance is 2% of the total mass of the solution or mixture.
v/v
an abbreviation for "by volume" which describes the concentration of a substance in a solution or mixture.
For example, 2% v/v means that the volume of the substance is 2% of the total volume of the solution or mixture.
