Understanding their mechanisms lets chemists alter reaction conditions to optimize the rate or the amount of a given product; the reversibility of the reaction and the presence of competing reactions and intermediate products complicate these studies.

• 化学家懂得反应机理后,可让他们改变反应条件以充分利用特定产物的速率和数量;反应的可逆性以及竞争反应、中间产物的存在使研究更加复杂。