An electrolyte is a substance that gains a positive or negative charge when dissolved in a solvent. Water is a highly effective solvent for producing electrolytes because of its polarity. Oxygen atoms being more electronegative than hydrogen atoms causes the electrons in water to give the oxygen molecules a partial negative charge and the hydrogen atoms a partial positive one.
Electrolytes in solutions are described as either concentrated or dilute depending on whether or not it has a high concentration of ions. Strong electrolytes are defined by a high proportion of free ions forming, and weak electrolytes by a lack of dissociation within the solute.