Question

$\alpha$-D-glucose undergoes mutarotation to $\alpha$-D-glucose in aqueous solution. If at 298 K there is 60% conversion, calculate $\Delta G^o$ of the reaction.
$\alpha -D-Glucose\rightleftharpoons \beta -D-Glucose$

• A. 0.525 kJ/mol
• B. 1.005 kJ/mol
• C. 2.45 kJ/mol
• D. None of these

Answer 1

Answer: (B)

1.005 kJ/mol

As given,
$\underset{a(1-0.6)}{{\alpha }^{-}}\rightleftharpoons \underset{0.6a}{{\beta }^{-}}$

Now,

$K_C=\frac{0.6}{0.4}=1.5$

$\Delta G^o=-RTln\left(K_c\right)$

$\Delta G^o=-8.314\times 298\times ln1.5J/mol$

$\Delta G^o=1.005kJ/mol$