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Elements on the periodic table are organized based on their atomic number, electron configurations, and recurring chemical properties, primarily into metals, nonmetals, and metalloids. Metals, which make up the majority of elements, are typically found on the left side and in the middle of the periodic table. They are known for being good conductors of heat and electricity, having a shiny luster, being ductile and malleable, and often having higher densities and melting points.

Nonmetals, on the other hand, are located on the upper right side of the periodic table. They are poor conductors of heat and electricity, and they often have lower densities and melting points than metals. The nonmetals include the halogens and noble gases, with noble gases like Element 118 (Oganesson) being distinct for their low reactivity due to a full valence electron shell. Metalloids have intermediate properties and serve as a bridge between metals and nonmetals on the periodic table.

Chemical bonding is the process by which atoms combine to form compounds. There are three primary types of chemical bonds: ionic, covalent, and metallic. Ionic bonding occurs between metals and nonmetals, where electrons are transferred from one atom to another, resulting in a lattice of positively and negatively charged ions. In covalent bonding, typically between nonmetals, atoms share electron pairs.

Metallic bonding, characteristic of metals, involves a 'sea' of delocalized electrons around a lattice of positively charged metal ions. This delocalization results in the high conductivity and malleability of metals. Understanding these bonding types is fundamental in predicting compound formation and behavior.

Ionic and covalent compounds differ significantly in their properties and formation. Ionic compounds form from the electrostatic attraction between oppositely charged ions, typically a metal cation and a nonmetal anion. Their structure is a crystal lattice which endows them with high melting and boiling points, and they often dissolve in water to form electrolytes.

Covalent compounds are formed by atoms that share electrons in pairs, usually between nonmetals. These compounds can exist as gases, liquids, or solids at room temperature and tend to have lower boiling and melting points than ionic compounds. They do not conduct electricity as solids but can do so if dissolved in water depending on their polarity.

Metallic and nonmetallic properties determine the reactivity and use of elements and their compounds. Metals typically have a shiny appearance, are heavy and dense, can be shaped (malleability), and drawn into wires (ductility). They tend to lose electrons during chemical reactions, forming positive ions.

Nonmetals have a more varied appearance, including gases like hydrogen, liquids like bromine, and solids like sulfur. They tend to gain or share electrons when reacting, often forming negative ions or covalent bonds. The variations in these properties across the periodic table enable a vast array of chemical reactions and compounds.