$H_2$$_{(g)} +$ $1/2O_2$ $_{(g)}$ $\rightarrow$ $H_2$$O$$_{(l)}$; $\Delta H= -$ $285.77\, KJ\, mol$$^{-1}$; $H_2$$_{(g)} +$ $1/2O_2$$_{(g)}$ $\rightarrow$ $H_2O$ $_{(g)}$; $\Delta H$ $ = - 241.84\, KJ \,mol$$^{-1}$
($\Delta H$ અને $\Delta S$ તાપમાન સાથે બદલાતા નથી તેમ ધારો)
${C_{\left( {graphite} \right)}} + {O_{2\left( g \right)}} \to C{O_{2\left( g \right)}}\,;\,\Delta H = -393.5\,kJ$
${C_2}{H_{4\left( g \right)}} + 3{O_{2\left( g \right)}} \to 2C{O_{2\left( g \right)}} + 2{H_2}{O_{\left( l \right)}}\,;\,\Delta H = - 1410.9\,kJ$
${H_{2\left( g \right)}} + 1/2{O_{2\left( g \right)}} \to {H_2}{O_{\left( l \right)}}\,;\,\Delta H = - 285.8\,kJ$