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各种学科和各种技能之间,或同一学科和技能的各个不同部分之间,都存在着某种程度的相互影响和联系。所以,一般来说掌握的知认越多,就越容易顺利地掌握新知识。因此在化学实验中应当重视运用各学科的知识。现举例如下: 一、利用物理学科中的金属是热的良导体的知识,做可燃气体的防爆装置。用一块铁丝窗纱(铜网更好)放在酒精灯或蜡烛的火焰上方,火焰只在窗纱的网眼下晃动,而不会透过网眼在上边燃烧。这是因为金属是热的良导体,金属丝将热量吸去,使酒精或蜡烛在金属网上方的蒸气达不到着火点。如将金属网先用火烧红(这时金属网不再吸收过多的热量),再放到燃着的酒精灯或蜡烛上方,其蒸气便可以透过金属丝的
There is some degree of mutual influence and connection between various disciplines and various skills, or between different parts of the same discipline and skill. Therefore, in general, the more knowledge you have, the easier it will be to acquire new knowledge. Therefore, in the chemical experiment, we should pay attention to the use of knowledge in various disciplines. Examples are as follows: First, the use of physics in the knowledge that the metal is a good conductor of heat, as a combustible gas explosion-proof devices. With a wire screen (better copper mesh) placed above the flame of an alcohol lamp or candle, the flame will only sway under the mesh of the screen, and will not burn through the mesh. This is because metal is a good conductor of heat and the wire sucks away heat, so that the vapor of alcohol or candles on the metal grid does not reach the ignition point. If the metal net is fired red first (in which case the metal net will no longer absorb excessive heat) and placed above the burning alcohol lamp or candle, the vapor can pass through the wire.