How can I convert percent concentration to ppm?

1 Answer
Jul 21, 2014

You multiply the % concentration by 10⁴.

% by mass = #"grams of solute"/(100"g soln")#

ppm = "grams of solute"/(10⁶"g soln")

You want to know how many grams of solute are in 10⁶ g of solution.

10⁶ g soln × (1"g solute")/(100"g soln") = 10⁴ g solute, or

(1"g solute")/(100"g soln") = (10⁴"g solute")/(10⁶"g soln")

1 × (1"g solute")/(100"g soln") = 10⁴ × (1"g solute")/(10⁶"g soln")

or

1 % = 10⁴ ppm

EXAMPLE PROBLEM

Convert a concentration of 0.241 % to parts per million.

Solution

0.241 % × (10⁴"ppm")/(1"%") = 2410 ppm