Given acids, alkanes, alkyl halides, amines, and alcohols, of comparable molecular mass, what is the probably order of volatility?

1 Answer
Mar 13, 2017

Answer:

We assess the degree of intermolecular force; the degree of interaction between individual molecules.

Explanation:

And thus in order of INCREASING boiling point, DECREASING volatility:

#"(i) alkanes; (ii) alkyl halides; (iii) amines; (iv) alcohols; (v) acid."#

Alcohols have a greater propensity to hydrogen bond than the amine, and are thus ranked higher: cf. #"ethyl alcohol", 78# #""^@C#, #"ethyl amine", 18# #""^@C#. Hydrogen bonding, the most potent intermolecular force, is decisive for carboxylic acids; cf. #"acetic acid", 118# #""^@C#.

As the alkyl chain grows, hydrophobic interactions become strong, and thus long chain alkanes, even without functionality, can have high boiling points.