Abstract For a chemical reaction only containing ideal gases, Gibbs free energy, changing with the extent of reaction, was obtained. In the equation of Gibbs free energy, three items were contained. The first item was the sum of Gibbs formation energy of reactants and products, defined as the temperature-controlled item. The second item was the contribution of pressure to the Gibbs energy, named as the pressure-controlled item. The third one was the mixed entropy, which was contribution of mixing degree between the reactants and the products to the Gibbs energy. For any chemical reaction, the reaction direction and the chemical equilibrium can be controlled by temperature and pressure. Take NH3 synthesis and industrial synthesis gases for examples, how to control the reaction direction and chemical equilibrium by the temperature and pressure was discussed in detail.
ZHANG Yun-Hong, PANG Shu-Feng, ZHENG Chuan-Ming. How to Control Chemical Reaction Direction and Chemical Equilibrium by Temperature and Pressure[J]. Chinese Journal of Chemical Education, 2019, 40(22): 91-95.