Question

If 0.250 L of aqueous solution with a density of 1.00 g/mL contains 13.7 g of pesticide, express the concentration of pesticide in (a) ppm and (b) ppb.

Answer 1

Since the density is 1.00 g/mL, that makes the mass of solution the same as the volume of the solution. My old standby is to know that 1 ppm = 1 mg/L. 13.7 g pesticide = 13.7 x 1000/250 = approx 55 mg/L = approx 55 ppm. That is the same as approx 55,000 ppb.

Answer 2

thanks!