For everywhere I've searched on books and internet, they all said solvent is generally larger in amount than solute. I wonder should I take the word "generally" seriously. And does the word "amount" means its "mass" or "no. of moles/no. of atoms/no. of ions"? Then as I'm learning acid & base. I found conc. HNO3 contains 65% by mass and conc. H2SO4 contains 98% by mass, so I wondered if they are solute because they ionizes or if there isn't really a fine line between solute and solvent.