covalenten

Covalenten, or covalent bonds, are chemical bonds formed by the sharing of one or more electron pairs between atoms. This sharing allows each atom to approach a noble-gas electronic configuration and is most common between nonmetal atoms with similar electronegativities, though some bonds exhibit polarity.

Bond types include single, double, and triple covalent bonds, corresponding to one, two, or three shared electron pairs. The strength and length of a covalent bond depend on the number of shared electrons and the participating atoms. Polar covalent bonds arise when electrons are shared unequally due to differences in electronegativity, while nonpolar covalent bonds occur when sharing is more even.

In terms of structure, covalent bonds involve sigma bonds from end-to-end orbital overlap, with additional pi bonds in multiple bonds. Covalent bonding influences molecular geometry through electron-pair repulsion, described by VSEPR theory. Some substances form extended covalent networks (such as diamond or quartz) with bonds throughout a lattice, whereas others exist as discrete molecules (for example H2, H2O, CH4).

Covalence, or valence in the covalent sense, reflects how many covalent bonds an atom tends to form. Common values include H with one, C with four, N with three, and O with two. In practice, elements can show variable covalence, especially in compounds with expanded octets or unusual oxidation states (such as sulfur in SF6). Covalent compounds are typically poor electrical conductors in the solid state but can conduct when molten or dissolved if they are polar or form ions.

Examples include H2, O2, NH3, CH4, H2O, CO2, and organic molecules like glucose (C6H12O6). Covalent bonding underpins the vast majority of chemistry in biology, organic chemistry, and materials science.