I was hoping to get some thoughts on this, figured this was a good place!
At work we test the composition of our materials by ICP-OES, using standards that we make up from single element solutions purchased from SCP Science.
For instance if we want to verify that a sample is 75% Metal A, and 25% Metal B. We make up a 10 mL standard in a volumetric with 7.5 mL of the single element solution for Metal A and 2.5 mL of the single element solution for Metal B.
It occurred to me today that we never factor in density, but our certification is for % composition by weight.
So if the Single Element solution for Metal B has a density of 1.037 g/mL, then 2.5 mL of that solution actually gives us 2.593 g of Metal B, and 7.64 g of Metal A.
Should we then be entering into the software that the standard is actually 25.93% of Metal B as opposed to 25%?