  Establishing quantitative correlations between various molecular properties
and chemical structures is of great technological importance for environmental
and medical aspects. These approaches are referred to as Quantitative
Structure-Property Relationships (QSPR), which relate the physicochemical or
thermodynamic properties of compounds to their structures. The main goal of
QSPR studies is to find a mathematical relationship between the property of
interest and several molecular descriptors derived from the structure of the
molecule. Topological indices are the molecular descriptors that characterize
the formation of chemical compounds and predict certain physicochemical
properties. In this study, the QSPR models are designed using certain
temperature-based topological indices such as the sum connectivity temperature
index, product connectivity temperature index, F-temperature index, and
symmetric division temperature index to predict the thermodynamic properties,
such as enthalpies of formation ($\Delta H^{0}_{f}$ \hspace{1mm} liquid),
enthalpies of combustion ($\Delta H^{0}_{C}$ \hspace{1mm} liquid), and
enthalpies of vaporization ($\Delta H^{0}_{vap}$ \hspace{1mm} gas) of
monocarboxylic acids ($C_2H_{4}O_{2}$ - $C_{20}H_{40}O_{2}$). The relationship
analysis between thermodynamic properties and topological indices is done using
linear, quadratic, and cubic equations of a curvilinear regression model. These
regression models are then compared.
