In a considerable number of cases plots of $T{\mathrm{\Delta }}^{‡}S$ vs. ${\mathrm{\Delta }}^{‡}H$, for a series of reactions, e.g. for a reaction in a range of different solvents, are straight lines of approximately unit slope. Therefore, the terms ${\mathrm{\Delta }}^{‡}H$ and $T{\mathrm{\Delta }}^{‡}S$ in the expression partially compensate, and $${\mathrm{\Delta }}^{‡}G={\mathrm{\Delta }}^{‡}H-T{\mathrm{\Delta }}^{‡}S$$ often is a much simpler function of solvent (or other) variation than ${\mathrm{\Delta }}^{‡}H$ or $T{\mathrm{\Delta }}^{‡}S$ separately.