What is Chemical bond?
[[File:Dihydrogen-phase-3D-balls.png|thumb|300x300px|The drawing on the left side, is supposed to show an example of one hydrogen nucleus that has a bond to another hydrogen nucleus. (No picture has been taken of a bond between two (hydrogen) atoms; There is no [[evidence]] of any [[expert]] having seen (with the expert's own eyes) a bond between two atoms.) Those two nuclei are inside the [[electron cloud]] (that is made of the electrons of both of these two hydrogen atoms). To show when two atoms have a [[covalent bonding]], one can put a line - on a drawing - between the nucleus of the one atom, and the nucleus of the other atom.<!--[[Covalent bonding]] of two [[hydrogen]] atoms to form a hydrogen molecule, {{Chem|H|2}}. In (a) the two nuclei are surrounded by a cloud of two electrons in the [[Bonding molecular orbital|bonding orbital]] that holds the molecule together. (b) shows hydrogen's [[Antibonding molecular orbital|antibonding orbital]], which is higher in energy and is normally not occupied by any electrons. Those two atoms (in that drawing), have a bond between them. T-->]] {{TopicTOC-Chemistry}} A '''chemical bond''' is a type of attraction force which holds together different [[chemical species]]. Atoms bonded stay together unless the needed amount of [[energy]] is [[energy transfer|transferred]] to the bond. In general, strong chemical bonding comes with the sharing or transfer of [[electrons]] between the participating atoms. The atoms in [[molecules]], [[crystals]], [[metals]] and diatomic [[gases]] are held together by chemical bonds. There are two types of bonds; covalent and ionic. [[Covalent bonds]] form when atoms share electrons. [[Ionic bond|Ionic bonding]] is the attraction between oppositely charged [[ions]]. Chemical bonds are negatively charged electrons that are pulling protons into each other. Because atoms and molecules are [[three-dimensional]], it is difficult to use a single method to indicate orbitals and bonds. In molecular formulas the chemical bonds between atoms are