We extend the subspace sampling method (SSM) to three dimensions to simulate the thermodynamic and structural properties of the weak electrolyte solution. We demonstrate that the subspace sampling method is particularly well-suited to investigate chemical reaction systems. The weak electrolyte system is simulated using the sticky electrolyte model with and without dipolar interactions. For low concentrations of electrolyte (0.0625 M), the simulated equilibrium association constant is insensitive to the inclusion of the dipolar interactions when the depth of the molecular potential (epsilon(2)/k(B)) is 4000 K and the width is 0.42 Angstrom. The internal energy of the molecule is the dominate source of stabilization energy; the dipolar interactions contribute only minimally to stabilize the system. The parameters chosen in these simulations are consistent with those used in the analytical solutions. However, the equilibrium constant computed from the Monte Carlo simulations and extrapolated to an infinite cell size is approximately 1 order of magnitude greater than that of the hypernetted chain/mean sphere approximation (HNC/MSA) or the HNC approximation, The simulated contact site-site correlation function is lower than both approximation methods when the dipolar interaction is included but resembles more closely the results of the HNC/MSA calculations.