Bubble formation with chemical reaction and mass transfer at a submerged orifice is analyzed theoretically. The phenomena of both hydrodynamics and mass transfer with chemical reaction are modeled successfully by the combination of the interfacial element approach and the penetration theory. Instantaneous bubble shapes, bubble volume and bubble growth rate simulated by the new model are in a good agreement with experimental data. Instantaneous liquid phase mass transfer coefficient, mass transfer rate from bubble surface, and gas-liquid contacting area are also predicted.