Illustrated Glossary of Organic Chemistry

Volatile: Evaporates easily. Sometimes also means flammable and/or explosive. Not all substances that evaporate readily are flammable or explosive (example: Halons). Not all substances that are flammable or explosive evaporate readily (example: TNT).

Time = 0 minutes
   
Time = 60 minutes
Acetone (bp 56 oC) is more volatile (evaporates more readily) than water (bp 100 oC). At the start each beaker contains 80 ml. After one hour elapsed time, the water remains at 80 ml (evaporation is negligible) but the acetone has evaporated down to 40 ml. Note condensation on the acetone beaker because evaporation is endothermic. Click here to see a time-lapse video.


An ether fire.
 Diethyl ether (CH3CH2OCH2CH3) is highly volatile. It has a boiling point of 34.6oC and evaporates readily at room temperature. It is highly flammable and its vapors easily explode.



Boiling water.
 Water (H2O) is moderately volatile. It has a boiling point of 100oC and evaporates only slowly at room temperature. It is not flammable or explosive.
                           


Table salt.
 Sodium chloride (NaCl; table salt) is not volatile. It has a boiling point of 1413oC and does not evaporate readily even at elevated temperatures. It is not flammable or explosive.