Question

PPM and PPB A 180-mg sample of Na2CO3 is dissolved in H2O to give 2.80L of solution. What is the concentration of Na+ in parts per million (ppm)? Note: "ppm" are 106 ×[(mass of solute)/(mass of solution)] ppm 1pts Tries 0/5 A 2.15-mg sample of dioctyl phthalate (C24H38O4), a plasticizer, is dissolved in H2O to give 550mL of solution. What is the concentration of dioctyl phthalate in parts per billion (ppb)? Assume U.S. definition of "one billion" = 109 (as opposed to British 1012). ppb 1pts

Answer 1

Ans :

A)

ppm = ( mass of solute / mass of solution ) x 10⁶

here the mass of solute is 180 mg and mass of solution is almost 2.80 kg = 2.8 x 10⁶ mg

So concentration in ppm :

= ( 180 / 2.8 x 10⁶) x 10⁶

= 64.3 ppm

B)

mass of solute = 2.15 mg

mass of solvent is almost 550 g = 5.5 x 10⁵ mg

ppb = ( mass of solute / mass of solvent) x 10⁹

= ( 2.15 / 5.5x10⁵) x 10⁹

= 3910 ppb