Chemical bonds are what joins atoms together. When two or more atoms are in a chemical bond they stay together unless the needed amount of energy, or more, is transferred to the bond. Something different can then happen.
Chemical bonds can be explained using different theories. Some of these theories try to explain chemical bonds in a simple way that can be used by chemists to imagine what could happen when they try to make molecules. Some explain how the atoms are bonded together with more detail and are used by chemists and physicists. There are two types of bonds; covalent and ionic. Covalent bonds form when atoms share electrons. Ionic bonding is the attraction between oppositely charged ions. Chemical bonds are negatively charged electrons that are pulling protons into each other.
The explanation of the attractive forces called "bonds" is a complex area that is described by the laws of quantum theory.
Bonds vary widely in their strength. Generally, the types of bonds referred to as covalent and ionic bonds are often described as "strong", whereas hydrogen bonds and van der Waals bonds are generally considered to be "weak".
Lewis Dot Style
A common way chemists describe chemical bonds is through the number of electrons each atom has on itself. Each atom is drawn with the number of electrons as dots to form a maximum of eight. The number of dots changes if there are less or more electrons. If the electrons form a chemical bond then a line is drawn between the two electrons.
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