新编初中化学课本第115页图3—9灭火器原理的演示实验。由于很多学校没有吸滤瓶而不能做。即使有吸滤瓶能做的,也由于导气管口较大,实验效果很差,不是喷出而是流出。并且还需牵绳引线等,操作也麻烦。我建议将该实验改为这样的装置(如图所示):即在一大号试管中注入约1/3试管高的H_2SO_4溶液,在一小号试管中注入NaHCO_3饱和溶液到离管口2厘米处,然后倾斜大号试管,将小号试管沿大号试管壁缓缓滑下底部,再在小试管中插入一小木梗(长短以距大号试管中2厘米为宜),最后用一带有直角尖嘴玻璃管的 New junior high school chemistry textbook page 115 Figure 3-9 Demonstration experiment of fire extinguisher principle. Since many schools do not have suction flasks, they cannot do it. Even if a suction filter bottle can do it, because of the large air-guiding nozzle, the experimental results are very poor. And also need to pull rope leads, etc., operation is also troublesome. I suggest to change this experiment to a device (as shown in the figure): Inject a solution of H_2SO_4 about 1/3 of the tube height in a large test tube, and inject a saturated solution of NaHCO 3 into the small test tube. 2 In centimeters, then tilt the large test tube, slowly slide the small test tube along the large tube wall down the bottom, and then insert a small wooden stem in the small test tube (length is 2 cm from the large test tube is appropriate), and finally use One with a right angle tip glass tube