Why do atoms form chemical bonds?

Question

Please summarise to me why atoms form chemical bonds.

Answer 1

Because energy comes from the outside that causes them to do so. Or because energy is given off when they do so. The important thing is that atoms seldom form chemical bonds. This is because there are seldom single atoms waiting around to form bonds. Rather, in actual experience, atoms are already bonded to one another, even in the elemental state: H2, F2, Cl2. Then they change their bonding patterns in response to energy input or because of release of energy. Beware of explanations that say that there is one electron lacking a complete shell, or one electron more than a complete shell. Atoms form chemical bonds because they were previously bonded differently.

Answer 2

At the risk of being anthromorphic, the energy generated from a chemical reaction is greater than the energy investment to to bond with another atom or group of atoms
.
Also note that there are atomic orbital bonds, which the atoms posess (or we think they posess by the Schroedinger probability solution) and hybrid bonds, which can be formed by "blending" atomic orbitals.

Answer 3

Most atoms have incomplete outer electron shells. These atoms are generally the ones that bond with others. They need to complete their outer shell, and to do this, they share some of their electrons between themselves (covalent bond) or take/give electrons from/to another atom and turn it into an ion in the process, attracting both ions together because of static electric charge (ionic bond).
Covalent bonds only happen between non-metals. For example, oxygen has 6 electrons in its outer orbit. When two oxygen atoms bond, they both share 4 (2 from each). Those 4 belong to both, and added to the other four that each keeps to itself, 4+4=8, which is the total number of electrons their outer orbit can hold.
Ionic bonds form between non-metals and metals. For example, a sodium atom (1 electron in its outer orbit) and a chlorine atom (7 electrons in its outer orbit) bond. Sodium gives its one outer electron and it left with an empty outer shell (meaning that the shell that's one shell lower is full) to chlorine, which gets a full 8-electron outer shell with its original 7 and the other electron from sodium. But, by taking an electron away, chlorine has left sodium with more protons than electrons, resulting in a positive charge for it, and chlorine has more electrons than protons, resulting in a negative charge for it. The two oppositely-charged atoms bond through electrostatic attraction.

Answer 4

chemical bonding rule

Answer 5

It's simple in principle. Atoms share electrons. Each one has a electric grip on the electron they share which has the effect of binding then together.