Which condition among the following holds true at the state of half-completion for the reaction $A…
Which condition among the following holds true at the state of half-completion for the reaction $A ightleftharpoons B$ ?
$\Delta G^{\circ}=0$
$\Delta G^{\circ}>0$
$\Delta G^{\circ} < 0$
$\Delta G^{\circ}=-R T \ln 2$
Solution
Equilibrium condition in the course of a reversible chemical reaction is in which no net change in the amounts of reactants and products occurs.
At equilibrium, the reaction is half completed, $[A]=[B]$
Thus, $\frac{[B]}{[A]}=1$
According to standard free Gibbs energy,
$$
\begin{aligned}
\Delta G^{\circ} & =-R T \ln K \\
\Delta G^{\circ} & =-R T \ln (1) \\
{\left[\Delta G^{\circ}ight.} & =0]
\end{aligned}
$$
Hence, at equilibrium condition, the reaction is half-completed i.e., $A ightleftharpoons B$.
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