નીચેની માહિતી પરથી $1.8\,^{\circ}C$ તાપમાને $Ca(OH)_{2(s)}$ ની નિર્માણ ઉષ્મા (heat of formation) ગણો:
$CaO_{(s)} + H_2O_{(l)} \to Ca(OH)_{2(s)}$; $\Delta H_{1.8\,^{\circ}C} = -15.26\,K\,cal$
$H_{2(g)} + \frac{1}{2}O_{2(g)} \to H_2O_{(l)}$; $\Delta H_{1.8\,^{\circ}C} = -68.37\,K\,cal$
$Ca_{(s)} + \frac{1}{2}O_{2(g)} \to CaO_{(s)}$; $\Delta H_{1.8\,^{\circ}C} = -151.80\,K\,cal$

• A
  $-98.69$
• B
  $-235.43$
• C
  $194.91$
• D
  $98.96$