Why do atoms need to form covalent bonds?

Answer 1

Covalent Bond Force holding atoms in a molecule together as a specific, separate entity (as opposed to, e.g., colloidal aggregates; see bonding). In covalent bonds, two atoms share one or more pairs of valence electrons to give each atom the stability found in a noble gas. In single bonds (e.g., H-H in molecular hydrogen), one electron pair is shared; in double bonds (e.g., O=O in molecular oxygen or H2C=CH2 in ethylene), two; in triple bonds (e.g., HCºCH in acetylene), three. In coordinate covalent bonds, additional electron pairs are shared with another atom, usually forming a functional group, such as sulfate (SO4) or phosphate (PO4). The number of bonds and the atoms participating in each (including any additional paired electrons) give molecules their configuration; the slight negative and positive charges at the opposite ends of a covalent bond are the reason most molecules have some polarity (see electrophile; nucleophile). Carbon in organic compounds can have as many as four single bonds, each pointing to one vertex of a tetrahedron; as a result, certain molecules exist in mirror-image forms (see optical activity). Double bonds are rigid, leading to the possibility of geometric isomers (see isomerism). Some types of bonds, such as the amide linkages that join the amino acids in peptides and proteins (peptide bonds), are apparently single but have some double-bond characteristics because of the electronic structure of the participating atoms. The configurations of enzymes and their substrates, determined by their covalent bonds (particularly the peptide bonds) and hydrogen bonds, are crucial to the reactions they participate in, which are fundamental to all life. http://www.answers.com/topic/covalent-bond?cat=health

Answer 2

So, A covalent bond forms when two non-metal atoms share a pair of electrons. The electrons involved are in the outer shells (highest occupied energy levels) of the atoms. An atom that shares one or more of its electrons will fill its outer shell.

Answer 3

Atoms need to form covalent bonds in order to share electrons so that they can achieve a stable electronic configuration.

Stability is the main reason of bonding between two substances in almost all the cases.

Exception:- When noble gases like Krypton, Xenon are made to react with other substances despite being stable.

Answer 4

Covalent bonds form between atoms of the same element or different elements.

Answer 5

Because the combination of atoms that forms the bond(s) has less overall energy after bonding than before.

Answer 6

Covalent bonds form molecules.