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钠跟水反应放出气体的收集和检验,按照师范化学第二册 P_(229)的操作,由于学生初次接触这样的操作,不够熟练,在试管中收集的氢气比较少,检验不出钠和水反应放出的气体是氢气,以致达不到实验的目的。为了使学生很方便地确认钠跟水反应确有氢气生成,特作如下改进.把一块橡皮塞制作成带有2个缺口的10mm厚的橡皮片,把它塞入18×150mm 的穿底坏试管中,并准备好带有尖口导管的橡皮塞一块,待用。实验时,用镊子取一颗绿豆粒大小的钠,用香烟包装纸——铝箔包好(事先用针在铝箔
The collection and examination of the gas evolved from the reaction of sodium with water, in accordance with the operation of Teacher’s Chemistry Book II P_(229), due to the initial exposure of students to such operations, not skilled enough, the collection of hydrogen in the test tube is relatively small, no sodium and water can be tested The gas evolved by the reaction was hydrogen so that the purpose of the experiment was not achieved. In order to make it easy for students to confirm that sodium reacts with water and does indeed produce hydrogen gas, special improvements are made as follows. A piece of rubber stopper is made into a 10mm thick rubber sheet with 2 notches, and it is stuffed into a 18×150mm bad bottom. In the test tube, prepare a piece of rubber stopper with a pointed catheter and wait. During the experiment, use tweezers to take a green bean size of sodium and wrap it in a cigarette wrapper—aluminum foil (previously with a needle in aluminum foil