\(C(s)\,\, + \,\,\frac{1}{2}\,{O_2}(g)\, \to \,CO(g),\,\Delta H\,\, = \,\, - \,110.5\,\,kJ\)
આ સમીકરણ માટે \(\Delta n\) \(=\) નિપજના વાયુમય મોલની સંખ્યા \(-\) પ્રક્રિયકોના વાયુમય મોલની સંખ્યા
\( = \,\,1\,\, - \,\,\frac{1}{2}\,\, = \,\, + \,\frac{1}{2}\,\)
\(R\, = \,\,8.314\,\, \times \,\,{10^{ - 3}}\,kJ/K/mol.,\,\,\,\,T\,\, = \,\,298\,K\)
હવે,\(\Delta H = \Delta E + \Delta n RT\)
\(\Delta\)\(E\) અચળ કદે પ્રમાણિત પ્રક્રિયા ઉષ્મા \(= ?\)
આથી \( - 110.5\,\, = \,\,\Delta E\,\, + \,\,( + \frac{1}{2})\,\, \times \,\,8.314\,\, \times \,\,{10^{ - 3}}\, \times \,\,{\text{298}}\)
\(\Delta {\text{E}}{\mkern 1mu} {\mkern 1mu} = {\mkern 1mu} {\mkern 1mu} {\text{( - 110}}{\text{.5}}{\mkern 1mu} {\mkern 1mu} {\text{ - }}{\mkern 1mu} {\mkern 1mu} \frac{{\text{1}}}{{\text{2}}}{\mkern 1mu} {\mkern 1mu} \times {\mkern 1mu} {\mkern 1mu} {\text{8}}{\text{.314}}{\mkern 1mu} {\mkern 1mu} \times {\mkern 1mu} {\mkern 1mu} {\text{1}}{{\text{0}}^{{\text{ - 3}}}}{\mkern 1mu} \times {\mkern 1mu} {\mkern 1mu} {\text{298)}}\,{\text{kJ/mol}}{\text{.}}\)
\( = \,\,{\text{( - 110}}{\text{.5}}\,\,{\text{ - }}\,\,{\text{1}}{\text{.238)}}\,\,{\text{kJ/mol}}{\text{.}}\,\, = \,\,{\text{ - 111}}{\text{.738}}\,\,\,{\text{kJ/mol}}{\text{. }}\)
પ્રક્રિયા $3 CaO +2 Al \rightarrow 3 Ca + Al _{2} O _{3}$ માટે પ્રમાણિત પ્રક્રિયા એન્થાલ્પી $\Delta_{ r } H ^{0=}$ .......... $kJ$
$(i)$ $N_2H_4$$_{(l)}$ $+$ $2H_2O_2$$_{(l)}$ $\rightarrow$ $N_2$$_{(g)}$ $+$ $4H_2O$$_{(l)}$; $\Delta r{H_1}^ \circ = - 818 \,kJ/mol$
$(ii)$ $N_2H_4$$_{(l)}$ $+$ $O_2$$_{(g)}$ $\rightarrow$ $N_2$$_{(g)}$ $+$ $2H_2O$$_{(l)}$; $\Delta r{H_2}^ \circ = - 622 \,kJ/mol$
$(iii)$ ${H_2}_{(g)}\,\, $+$ \,\,\frac{1}{2}\,{O_2}_{(g)}\,\, \to \,\,{H_2}O_{(l)}\,\,\,;\,\,{\Delta }r{H_3}^ \circ \, = \,\, - 285\,\,kJ/mol$
$3 HC \equiv CH _{( g )} \rightleftharpoons C _{6} H _{6(\ell)}$
[આપેલ : $\Delta_{f} G ^{\circ}( HC \equiv CH )=-2.04 \times 10^{5}\, J mol ^{-1}$
$\Delta_{f} G ^{\circ}\left( C _{6} H _{6}\right)=-1.24 \times 10^{5}\, J mol ^{-1} ; R =8.314\,\left. J K ^{-1} mol ^{-1}\right]$
$C$ $($હીરા$)$ $ + {O_2}(g) \to C{O_2}(g);\,\Delta H = - 393.5$
જો ગ્રેફાઇટથી હીરો બને તો ઉપરના આંકડા પરથી $\Delta H$.......$kJ$
$\frac{1}{2}C{l_2}_{(g)}\,\xrightarrow{{\frac{1}{2}{\Delta _{diss}}{H^\Theta }}}\,Cl_{(g)}\,\,\xrightarrow{{{\Delta _{eg}}{H^\Theta }}}\,\,C{l^ - }_{(g)}\,\xrightarrow{{{\Delta _{hyd}}{H^\Theta }}}\,C{l^ - }_{(aq)}$
$({\mkern 1mu} {\Delta _{diss}}{\mkern 1mu} H_{C{l_2}}^\Theta {\mkern 1mu} = {\mkern 1mu} {\mkern 1mu} 240{\mkern 1mu} {\mkern 1mu} kJ{\mkern 1mu} {\mkern 1mu} mo{l^{ - 1}},{\mkern 1mu} {\mkern 1mu} {\Delta _{eg}}{\mkern 1mu} H_{Cl}^\Theta {\mkern 1mu} = {\mkern 1mu} {\mkern 1mu} - 349{\mkern 1mu} {\mkern 1mu} kJ{\mkern 1mu} {\mkern 1mu} mo{l^{ - 1}},{\mkern 1mu} {\mkern 1mu} $
${\Delta _{hyd}}H_{C{l^ - }}^\Theta {\mkern 1mu} = {\mkern 1mu} {\mkern 1mu} - {\mkern 1mu} 381{\mkern 1mu} kJ{\mkern 1mu} {\mkern 1mu} mo{l^{ - 1}})$