So the exercise gave us the concentration of a solution (1,5 x 10^-3 M) and the volume (10 mL).
The 1st part of the exercise was to calculate the amount of volume we need from a more concentrated solution (0,010 M). I calculated the volume which is 1,5 mL.
The solution is from CoCl2.6H2O.
Now they want us to pass the concentration of our prepared solution to ppm. How can I do that? Thanks!