# How do you calculate DeltaG for a reaction from DeltaH and DeltaS values?

$\Delta \text{G"=Delta"H"^@-"T"Delta"S}$
Also, $\Delta \text{S}$ is given in $\text{J}$ ${\text{K}}^{-} 1$ ${\text{mol}}^{-} 1$, thus it must be converted into $\text{kJ}$ ${\text{K}}^{-} 1$ ${\text{mol}}^{-} 1$, otherwise the $\Delta \text{G}$ value will be incorrect.