0.000333 g fluorescein (332.32 g/mol) is dissolved in 225 ml solution of ethanol. the density of ethanol is 0.785 g/ml.
what is the concentration of the solution in molarity (m)?
how many ppm? i already know that the molarity is 4.45e-6. i just need on trying to find the ppm .

Parts per million of a solution is the mass fraction. It denotes the amount of one substance in one million parts of the other. Now, we can calculate the mass of the ethanol solution using its density and volume.
mass = density x volume
= 0.785 x 225
= 176.625 g
0.000333 : 176.625 = x : 1,000,000
x = (0.000333/176.625) * 1000000
x = 1.89 parts per million

Because a model would make the investigation easier to understand