Question

If the Gibbs free energy of the ΔG= Glc - Gg liquid-crystalline phase for an aqueous dispersion of DPCC and raffinose is 17.9 kcal/mol, which of the following values is nearest the Gibbs free energy of the associated gel phase?
A. 3.5 kcal/mol
B. 32.3 kcal/mol
C. 566.1 kcal/mol
D. 601.9 kcal/mol

Answer 1

Answer:

The answer is A. 3.5 kcal/mol

Explanation:

Δ$G = Glc - Gg$

Gibb free energy for phase transition of raffinose is

Δ$G =$ Δ$H - T$Δ$S$

Δ$G = (16.0kcal/mol) - [(3.15 * 102k) (5.05 * 10 - 3 kcal/k.mol)]$

Δ$G = 16.0kcal/mol - 1.60kcal/mol$

Δ$G = 14.4kcal/mol$

$Gg = Gl -$Δ$G$

$Gl = 17.9kcal/mol$

Δ$G = 14.4kcal/mol$

Substituting value

$Gg - Gl -$Δ$G$

$Gg = 17.9kcal/mol - 14.4kcal/mol$

Therefore,

$Gg = 3.5kcal/mol$