Spatial structure of molecules - isomerism

Spatial structure of molecules - isomerism

We are searching data for your request:

Forums and discussions:
Manuals and reference books:
Data from registers:
Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.

Structure Theory in Organic Chemistry

In order to understand how molecules behave, it is important to know their spatial structure. For example, are the atoms in a molecule arranged linearly, or are the molecules angled? Are they flat or three-dimensional? Since the molecules are not visible, their structure must be inferred indirectly. The structure of the molecules is therefore deduced from the behavior of the molecules. First, of course, it is important to know which atoms and how many are each in a molecule. The information obtained from elemental analysis of many compounds about the type and relationship of the elements to one another led to the following general findings:

  • Atoms only form a certain number of bonds in compounds. The measure for this is called valence.
Tab. 1



Carbon can form four bonds and is tetravalent



Oxygen is divalent


Boron trifloride

Boron is trivalent


Hydrogen chloride

Hydrogen and the halogens are monovalent

  • The element carbon can use one or more valences for bonds to other carbon atoms. So it can bond with itself and multiple bonds with itself and its valence can therefore be different.

Ethane has a carbon-carbon single bond, ethene has a double bond, and ethyne has a triple bond.