Trends in Boiling Points of Organic Compounds

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At a certain temperature, vapour pressure of a given liquid reaches a point equivalent to
pressure of its surrounding. This temperature is defined as the boiling point of such a
substance. Organic compounds exhibit a fascinating trend since they tend to have boiling
points based upon certain characteristics particular to every organic compound. According to
Burger, Baibourine, Bruno (2011 p.89), organic compounds comprises of a number of forces
that keep the molecules together. These forces include bonds of either ionic, hydrogen
bonding as well as van der Waal forces of attraction or the dipole to dipole moments or both.
Of all the forces, it has been noted that ionic bonds provides the greatest forces of attraction
hence substances possessing it considerably than other exhibit higher boiling points. After
ionic forces of attraction/bonds, hydrogen bonds ranks second followed by dipole-dipole
forces with the van der Waal forces of attraction being ranked as the weakest of all hence
associated with lowest boiling points in substances in which it occurs compared to the
aforementioned forces respectively. For instance, substances having OH groups including the
carboxylic acids has been identified to have high values of boiling points when compared to
substances having the COH, that is the aldehydes possessing the dipole-dipole bonds.
As per Burger et al (2011 p.121), atomic structure of the particles influences the surface zone
of the atoms which thusly influences the Van der Waals scattering influences and
consequently, the boiling points of the atoms. A long chain natural compound builds the
surface region of the atom and the sub-atomic weight of the particle. Henceforth, the capacity
of the individual particles to draw in one another is additionally expanded. The cooperation
result in expanded scattering effects and along these lines higher boiling points.
Compound structure (Haynes, 2014 p.87).

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Branched molecular structures anyway diminish boiling points of compounds as the surface
zone will be diminished and subsequently, the scattering forces too will be debilitated.
Compound structure (Haynes, 2014 p.132)
The last sub-atomic structure viewpoint influencing boiling point of the substances is the
introduction of the polar group of functionality. As indicated by Haynes (2014 p.192), an
uncovered polar assembly like in the carboxylic acids expands boiling points.
The compound structure of the alcohol (Kerth, 2016 p.78).

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Results (Kerth, 2016 p.108).
Name of the organic
compound.
Molecular Structure. Boiling Point.
Butanoic Acid C4H8O2 164.30C (Royal
Society of
Chemists, 2015)
Pentanal C5H10O 103.70C (Royal
Society of
Chemists, 2015)
Butane C4 H10 -0.5ᵒC
(Cleveland and
Morris, 2013)
1-butene C4 H8 -6.3ᵒC
(Cleveland and
Morris, 2013)