For a reversible reaction, the equilibrium constant can be measured at a variety of temperatures. This data can be plotted on a graph with  on the -axis and  on the  axis. The data should have a linear relationship, the equation for which can be found by fitting the data using the linear form of the Van 't Hoff equation
This graph is called the "Van 't Hoff plot" and is widely used to estimate the enthalpy and entropy of a chemical reaction. From this plot,  is the slope, and  is the intercept of the linear fit.
By measuring the equilibrium constant, , at different temperatures, the Van t Hoff plot can be used to assess a reaction when temperature changes. Knowing the slope and intercept from the Van t Hoff plot, the enthalpy and entropy of a reaction can be easily obtained using
The Van t Hoff plot can be used to quickly determine the enthalpy of a chemical reaction both qualitatively and quantitatively. This change in enthalpy can be positive or negative, leading to two major forms of the Van t Hoff plot.