$CaO_{(s)}\,\, + \,\,{H_2}O_{(l)}\,\, \to \,\,Ca{(OH)_2}_{(s)}\,;\,\,\,........(i)$ $\,\Delta {H_{1.8\,^oC}} = \,\, - \,\,15.26\,\,K\,cal$
$H_2O_{(l)}\,$ $ \to $ ${H_{2{(g)}}}$ $+$ $\frac{1}{2}O_{2(g)}$ $\,\Delta {H_{1.8\,^oC}} = \,\, - \,\,68.37\,\,K\,cal$
$Ca_{(s)} + \frac{1}{2}O_{2(g)} = CaO_{(s)}$ $\,\Delta {H_{1.8\,^oC}} = \,\, \,\,-151.80\,\,K\,cal$
પદાર્થ | $H _{2}$ | $C$(ગ્રેફાઈટ) | $C _{2} H _{6}( g )$ |
$\frac{\Delta_{ C } H ^{\Theta}}{ kJmol ^{-1}}$ | $-286.0$ | $-394.0$ | $-1560.0$ |
તો,ઈથેનની સર્જન એન્થાલ્પી ........