Separation of a mixture Lab - SiO2, NaCl, NH4Cl

Question

So step #7 was: Carefully pour off (decant) the liquid into the second evaporation dish, Adding deionized water in small amounts to the first dish and to stir it, and pour the liquid again into the second dish. Repeating it.

The question I'm having trouble with is, Suppose that not all of the NaCl dissolved in the water, explain this error would affect your reported percent of :
NH4Cl
NaCl
SiO2

Answer 1

I don't know enough about how you separated this mixture to answer. I may be able to help if you type in the entire procedure.