Question

How can I convert percent concentration to ppm?

Answer 1

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