$A + B \rightleftharpoons C+D$
$27^{\circ}\,C$ પર પ્રમાણિત મુક્ત ઊર્જા ફેરફાર $\left(\Delta_{ r } G ^0\right)$ $(-)$ $............kJ mol ^{-1}$ છે. (નજીકની પૂર્ણાંક)
(આપેલ : $R =8.3\,Jk ^{-1}\, mol ^{-1}$ અને In $10=2.3$ )
$\text { and } K _{ eq }=\frac{ K _{ f }}{ K _{ b }}$
$\therefore K _{ eq }=\frac{10^3}{10^2}=10$
$\therefore \Delta G =- RT \ln 10$
$\Rightarrow-(8.3 \times 300 \times 2.3)=-5.7\,kJ\,mole ^{-1} \approx 6\,kJ$
$\text { mole }{ }^{-1}(\text { nearest integer) }$
$\text { Ans }=6$
${C_{\left( {graphite} \right)}} + {O_{2\left( g \right)}} \to C{O_{2\left( g \right)}}\,;\,\Delta H = -393.5\,kJ$
${C_2}{H_{4\left( g \right)}} + 3{O_{2\left( g \right)}} \to 2C{O_{2\left( g \right)}} + 2{H_2}{O_{\left( l \right)}}\,;\,\Delta H = - 1410.9\,kJ$
${H_{2\left( g \right)}} + 1/2{O_{2\left( g \right)}} \to {H_2}{O_{\left( l \right)}}\,;\,\Delta H = - 285.8\,kJ$