在设计实验时，为保证实验科学、安全、成功，需注意以下几点：a．防倒吸。①在吸收易溶于某液体的气体（如用水吸收NH３，HX）或蒸气（如用饱和Na２CO３溶液吸收乙酸乙酯蒸气）时，为防止因气体大量溶于液体，而造成装置内压强减小，液体倒吸，使实验失败，常需设置防倒吸装置 In the design of experiments, in order to ensure scientific, safe and successful experiments, the following points must be noted: a. Anti-back suction. 1 When absorbing gas that is easily soluble in a liquid (such as absorbing NH3, HX with water) or vapor (such as absorbing ethyl acetate vapor with saturated Na2CO3 solution), the pressure inside the device is reduced to prevent the gas from being dissolved in a large amount in the liquid. , The liquid sucks backwards, causes the experiment to fail, often needs to install the anti- sucks and sucks the device