A reference solution is to be prepared
with 5 PPM parabenzopyrene
(molecular weight = 252). The quantity
of parabenzopyrene required for
preparing one litre 5 PPM solution is
To calculate the quantity of parabenzopyrene required for preparing a one-liter 5 PPM (parts per million) solution, we need to know the definition of PPM.
PPM is a unit commonly used to express the concentration of a substance in a solution. It represents the number of parts of the substance per one million parts of the solution. In other words, if we have a 5 PPM solution, we have 5 parts of the substance per one million parts of the solution.
To calculate the quantity of parabenzopyrene required for a one-liter solution, we will use the following formula:
Quantity (in grams) = (Desired concentration in PPM * Volume of solution in liters * Molecular weight of substance) / 1,000,000
Substituting the given values:
Quantity = (5 * 1 * 252) / 1,000,000
Quantity = 1.26 / 1,000,000
Quantity = 0.00000126 grams
Therefore, to prepare a one-liter 5 PPM parabenzopyrene solution, you would need approximately 0.00000126 grams of parabenzopyrene.