Many inorganic compounds are ionic compounds, consisting of cations and anions joined by ionic bonding. The abundant inorganic elements act as ionic electrolytes. Polyionic polymers are polymers with an ionic functional group. Bonds with partially ionic and partially covalent character are called polar covalent bonds. Potassium in nature occurs only in ionic salts. Chemical bonds can be grouped into two types consisting of ionic and covalent. Like carbon, nitrogen tends to form ionic or metallic compounds with metals. The tetrafluorides show a mixture of ionic and covalent bonding. Cellulose is also soluble in many kinds of ionic liquids. Precipitating seals enhance chemical stability but are less effective in eliminating ionic exchange pathways. It is a solvent for many ionic compounds. Driver designs include dynamic, electrostatic, plasma, ribbon, planar, ionic, and servo-actuated. Metal chlorides are largely ionic in nature. Metal iodides are predominantly ionic in nature. Dilute solutions follow Kohlrausch's Laws of concentration dependence and additivity of ionic contributions.