Editing Quantitative structure–activity relationship (section)

=== Chemical ===

One of the first historical QSAR applications was to predict [[boiling point]]s.<ref name="isbn0-85626-454-7">{{cite book | vauthors = Rouvray DH, Bonchev D | title = Chemical graph theory: introduction and fundamentals | publisher = Abacus Press | location = Tunbridge Wells, Kent, England | year = 1991 | isbn = 978-0-85626-454-2 }}</ref>

It is well known for instance that within a particular [[chemical classification|family]] of [[chemical compound]]s, especially of [[organic chemistry]], that there are strong [[correlation]]s between structure and observed properties. A simple example is the relationship between the number of carbons in [[alkanes]] and their [[boiling point]]s. There is a clear trend in the increase of boiling point with an increase in the number carbons, and this serves as a means for predicting the boiling points of [[higher alkanes]].

A still very interesting application is the [[Hammett equation]], [[Taft equation]] and [[Acid dissociation constant|pKa prediction]] methods.<ref name="RMC_2013">{{cite encyclopedia | last = Fraczkiewicz | first = R | encyclopedia = Reference Module in Chemistry, Molecular Sciences and Chemical Engineering [Online] | editor-last = Reedijk | editor-first = J | volume = 5 | publisher = Elsevier | location = Amsterdam, the Netherlands | year = 2013 | doi = 10.1016/B978-0-12-409547-2.02610-X | title = Reference Module in Chemistry, Molecular Sciences and Chemical Engineering | isbn = 9780124095472 | chapter = In Silico Prediction of Ionization }}</ref>