What makes rubbing alcohol and perfume evaporate?
Rubbing alcohol evaporates readily because at room temperature
it has a "high vapor pressure." That mean that molecules
of alcohol have a pretty high probability of escaping from the
the liquid surface. In order for this to be so, the
intermolecular attractive forces must be fairly weak
compared to the energy the alcohol is absorbing from its
container and the surrounding environment in the form of heat.
On the other hand, water-water forces are relatively strong, and
so its vapor pressure tends to be lower than that of alcohol
(i.e., water is less volatile).
I could go into more detail about hydrogen bonding and so forth
but that's the bottom line.
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Update: June 2012