Editing Molecular geometry (section)

== Isomers ==

[[Isomer]]s are types of molecules that share a chemical formula but have difference geometries, resulting in different properties:
* A '''pure''' substance is composed of only one type of isomer of a molecule (all have the same geometrical structure).
* [[Structural isomerism|Structural isomers]] have the same chemical formula but different physical arrangements, often forming alternate molecular geometries with very different properties. The atoms are not bonded (connected) together in the same orders.
** [[Functional isomer]]s are special kinds of structural isomers, where certain groups of atoms exhibit a special kind of behavior, such as an ether or an alcohol.
* [[Stereoisomer]]s may have many similar physicochemical properties (melting point, boiling point) and at the same time very different [[biochemistry|biochemical]] activities. This is because they exhibit a [[handedness]] that is commonly found in living systems. One manifestation of this [[Chirality (chemistry)|chirality]] or handedness is that they have the ability to rotate polarized light in different directions.
* [[Protein folding]] concerns the complex geometries and different isomers that [[protein]]s can take.