Volatile means changing phase from
liquid to gaseous state. We should consider boiling points of all
these 8 species. As propyl is not a compound it is a group it will
not exist alone. Examples are propyl alcohol, propyl chloride,
propyl bromide, propyl iodide, propyl cyanide etc. Boiling point
physical properties are used to make this determination.
Substance                   Â
Boiling Point
1.
hydrogen                  Â
-252 oCÂ Â ----------------------------- most
volatile
2.
methane                   Â
-161.5 oC
3.
ethylene                   Â
-103.7oC
4.
ethane                      Â
-89 oC
5.
propylene                  Â
-47.6 °C
6.
propane                    Â
-42 oC
7.
benzene                   Â
+80.1 oC
8.
toluene                     Â
+110.6 oC
9.
p-xylene                   Â
+138.4 oCÂ Â
10.
cumene                   Â
+152.4 oC ----------------------------- least
volatile
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