Question

1. 0.0050 grams of a chemical is dissolved in 75 grams of water. 

What is the concentration of the chemical in parts per million? 

Answer 1

solute = 0.0050g

solvent = 75g

concentration in ppm = $\dfrac{solute}{(solute + soluvent)}X 1 000 000$

concentration in ppm = $\dfrac{0.0050g}{(0.0050g + 75g)}$ x 1000000 = 66.66ppm