$3 HC \equiv CH _{( g )} \rightleftharpoons C _{6} H _{6(\ell)}$
[આપેલ : $\Delta_{f} G ^{\circ}( HC \equiv CH )=-2.04 \times 10^{5}\, J mol ^{-1}$
$\Delta_{f} G ^{\circ}\left( C _{6} H _{6}\right)=-1.24 \times 10^{5}\, J mol ^{-1} ; R =8.314\,\left. J K ^{-1} mol ^{-1}\right]$
$(i)\,\,\Delta H_f^o\,\,of\,{H_2}{O_{(\ell )}}\, = \,\, - 68.3\,K\,\,cal\,\,mo{l^{ - 1}}$
$(ii)\,\,\Delta H_{comb}^o\,\,of\,{C_2}{H_2}\, = \,\, - 337.2\,K\,\,cal\,\,mo{l^{ - 1}}$
$(iii)\,\,\Delta H_{comb}^o\,\,of\,\,{C_2}{H_4}\,\, = \,\, - \,363.7\,\,K\,\,cal\,\,mo{l^{ - 1}} $
કયા ન્યૂન્નતમ તાપમાને તે સ્વયંભૂ (આપ મેળે) થશે તે ............ $K$ માં છે. (પૂર્ણાક)