$N{H_{3(g)}}\, + \,\,\frac{3}{2}\,Cu{O_{(s)}}\, \to \,\,\frac{1}{2}\,{N_{2(g)}}\, + \,\,\frac{3}{2}{H_2}{O_{(\ell )}}\, + \,\,\frac{3}{2}\,C{u_{(s)}}.$ ......$J$
$\Delta \,H\,\, = \,\,\Sigma \,\,{H_{\ Products}}\,\, - \,\,\,\Sigma \,{H_{\operatorname{Reactants}}}$
$\because \,\,H_{element}^ \circ \,\, = \,\,0$
$\therefore \,\,\Delta \,H\,\, = \,\,\frac{3}{2}\,H_{{H_2}O}^o \,\, - \,\,H_{N{H_3}}^o \, - \,\,\frac{3}{2}\,H_{CuO}^o $
$ = \,\,\frac{3}{2}\,\, \times \,\,( - 285)\, - \,( - 46)\, - \,\,\frac{3}{2}\,( - 155)\,\,\,\,\,\,\,\,\,\,\, = \,\, - 149\,\,KJ$
$\because \,\,17\,\,gm\,\,N{H_3}$ ના ફેરફાર જોતાં $\Delta \,\,H\,\, = \,\, - \,149\,\,KJ$
$\,6.8\,\,gm\,\,N{H_3}\,$ ના ફેરફાર જોતાં $\Delta H\,\, = \,\, - \frac{{149}}{{17}}\,\, \times \,\,6.8\,\,KJ$
$ = \,\, - 59.6\,\,KJ\,\,\,\,\,\,\,\,\,\,\,\Delta \,H\,\, = \,\, - \,\,59.6\,\,KJ$
${N_2} + 3{H_2} \to 2N{H_3}$
જો $\Delta H$ અને $\Delta U$ અનુક્રમે પ્રક્રિયા માટેના એન્થાલ્પી ફેરફાર અને આંતરિક ઊર્જા ફેરફાર હોય, તો નીચેનામાંથી કઇ રજૂઆત સાચી છે ?
$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}$