A model for assessment and computational analysis of the concentration of zinc dissolved during leaching of sphalerite in butanoic acid solution has been derived. The model Zn = Antilog [(exp(γ/α))^0.6173] is dependent on the initial and final pH of the leaching solution. The validity of the model was found to be rooted in the expression (Log Zn)^1.62 = exp(γ/α) where both sides of the expression are approximately equal to 3. The maximum deviation of the model-predicted concentrations of dissolved zinc from that of the corresponding experimental values is less than 14% which is quite within the acceptable deviation limit of experimental results.