Here's where things get fun. Just like the number of reps, 3-6 sets is the best range of volume for this training method. If you like your workouts paced like clockwork, take 30-60 seconds rest between each exercise.
The natural attraction between positive and negative keeps the ions surrounded by water molecules and therefore dissolved in solution. Many biochemicals are either polar molecules or charged ions (or both) so water makes an excellent solvent for them.
A very important solvent in nature and biology is water. Aqueous solutions are solutions containing water as the solvent. Many solutes can dissolve in water, and that is why water is the universal solvent. When a solution is formed, forces between particles in the solute and in the solvent are overcome. At the same time, new attractive forces are formed. The forces that are formed in a solution must be a similar strength as the forces overcome in the solute and solvent.