How can I convert percent concentration to ppm?

1 Answer
Jul 21, 2014

You multiply the % concentration by 10⁴.

% by mass = #"grams of [solute](http://socratic.org/chemistry/solutions-and-their-behavior/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