6. what are the units used to specify the solubility of a substance?
14. how is the concentration of 2 or more liquids expressed as a percentage? Is it mass of volume?
It could be mols/L or molarity. It also could be g/L or a similar unit.
14. It could be expressed three ways; i.e., mass percent (w/w); mass per unit volume (w/v) or as volume/volume percent.