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在初中化学课本里,有以下一些内容我认为是值得商榷的。一、图4-13钠跟水起反应的装置图。这个图里漏斗颈高出烧杯水面太多。如果按照它做装满水的试管,怎样套入漏斗颈呢?实际上,漏斗颈应该低于烧杯内的水面(稍高于烧杯内的水面,如果将烧杯倾斜时水平面能溢过漏斗颈也可以),这样装满水的试管,试管口用拇指堵住倒置,使装满水的试管浸入烧杯内水面以下,再套入水面以下的漏斗颈,试管内的水才不致于流出。
In junior school chemistry textbooks, there are some of the following items that I think are debatable. I. Figure 4-13 shows a device for reacting sodium with water. In this figure the funnel neck is too high above the beaker’s surface. If it is filled with water in accordance with the test tube, how to nest into the funnel neck? In fact, the funnel neck should be lower than the water inside the beaker (a little higher than the water inside the beaker, if the beaker tilted when the level can overflow the funnel neck also Can)), so filled with water in the test tube, test tube mouth blocked with a thumb upside down, so that the tube filled with water immersed in the water below the beaker, and then nested into the funnel below the surface of the water, the test tube of water will not flow out.