Editing Organic chemistry (section)

==Melting and boiling properties==

Organic compounds typically melt and many boil. In contrast, while inorganic materials generally can be melted, many do not boil, and instead tend to degrade.  In earlier times, the melting point (m.p.) and boiling point (b.p.) provided crucial information on the purity and identity of organic compounds.  The melting and boiling points correlate with the polarity of the molecules and their molecular weight.  Some organic compounds, especially symmetrical ones, [[Sublimation (phase transition)|sublime]].  A well-known example of a sublimable organic compound is [[1,4-Dichlorobenzene|''para''-dichlorobenzene]], the odiferous constituent of modern mothballs.  Organic compounds are usually not very stable at temperatures above 300&nbsp;°C, although some exceptions exist.

===Solubility===
Neutral organic compounds tend to be [[hydrophobic]]; that is, they are less [[soluble]] in water than in organic solvents.  Exceptions include organic compounds that contain [[ionizable]] groups as well as low [[molecular weight]] [[Alcohol (chemistry)|alcohol]]s, [[amine]]s, and [[carboxylic acid]]s where [[hydrogen bonding]] occurs.  Otherwise, organic compounds tend to dissolve in organic [[solvent]]s.  Solubility varies widely with the organic solute and with the organic solvent.

===Solid state properties===

Various specialized properties of [[Molecular solid|molecular crystals]] and [[Polymer|organic polymers]] with [[conjugated system]]s are of interest depending on applications, e.g. thermo-mechanical and electro-mechanical such as [[piezoelectricity]], electrical conductivity (see [[conductive polymer]]s and [[organic semiconductor]]s), and electro-optical (e.g. [[non-linear optics]]) properties.  For historical reasons, such properties are mainly the subjects of the areas of [[polymer science]] and [[materials science]].