Jean-David Beyer wrote:

If it is simply a matter of measuring a small amount of something, make
a 1% solution of whatever it is and use only a few millilitres of it.

Very good point. And I will add that dissolving something to make a
solution is important. If a chemist says 'stir', he means it. Don't
shake: stir. (I wonder if everyone got the feeling I did when first
mixing Rodinal 1:200. "Is it really in there?" Now I just drop it into
the water and it incorporates within a minute.)

Were I mixing a litre of some solution that needed only 0.001 gram of
something, I bet the solution would work the same without it.

Ah, but you aren't making nerve poison!