For an ideal solution containing two liquid components A and B, the Gibb's free energy of mixing is — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

The Gibbs free energy of mixing for an ideal solution is: ΔG_mix = n_total * R * T * (X_A * ln(X_A) + X_B * ln(X_B)). Since X_B = 1 - X_A, we can differentiate this expression with respect to X_A and set it to zero to find the minimum. This occurs exactly at X_A = 0.5, meaning X_A = X_B = 0.5. Thus, the molar ratio of A:B is 1:1.