Hi everyone,

Thanks a lot for your feedback. It seems that there does not exist an analytical solution. I also tried to solve the system of equations but without success.

For my particular task, I tried to denote x = [A], y = [B]. Then, in equilibrium state:

[itex][AB] = K_1 x y[/itex]

[itex][AA] = K_2 x^2[/itex]

[itex][BB] = K_3 y^2[/itex]

(1) [itex]x + K_1 x y + 2 \times K_2 x^2 = A_0[/itex]

(2) [itex]y + K_1 x y + 2 \times K_3 y^2 = B_0[/itex]

Mathematica spits out three solutions for this system -- each two-pages long. None of them seems right to me. Trying to substitute Ao, Bo, K1, K2, K3 with some real numbers results in gibberish -- complex numbers or numerical errors (like division by zero, etc.)

I tried to formulate problem differently, by denoting x = [AB], y = [AA], z = [BB]. Then,

[itex][A] = A_0 - x - 2y[/itex]

[itex][B] = B_0 - x - 2z[/itex]

(1) [itex]K_1 = \frac {x} {(A_0 - x - 2y)(B_0 - x - 2z)}[/itex]

(2) [itex]K_2 = \frac {y} {(A_0 - x - 2y)^2}[/itex]

(3) [itex]K_3 = \frac {z} {(B_0 - x - 2z)^2}[/itex]

Then solve for x, y, z. Nothing good happens here too...