现行高中化学课本中介绍的“卤素活动性比较”的两个演示实验,需要将有关药品配成一定浓度的溶液并需反复操作几次才能完成.另外,由于反应一般在小试管中进行,置换出来的少量的溴和碘又都需要萃取在有机溶剂中,因此能见度较低,坐在后面几排的同学往 The two demonstration experiments of “active activity comparison of halogens” introduced in the current high school chemistry textbooks require that the relevant drugs be formulated into a certain concentration of solution and must be repeatedly operated several times to complete. In addition, since the reaction is generally performed in a small test tube The small amounts of bromine and iodine that are displaced need to be extracted in organic solvents, so the visibility is low and the students in the back row are sitting