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书写化学方程式是中考的高频考点。不少同学在书写化学方程式时,经常会出现这样或那样的错误。如何正确地书写化学反应方程式呢?一、尊重反应事实,不能主观臆造和随意类推化学方程式是化学反应的真实记录,什么物质发生反应生成什么物质,这些都是客观存在的事实。因此书写化学方程式必须有根有据,绝不可想当然胡编乱造或机械模仿,更不能随意类推。例如,学习了2KClO_3(?)2KCl+3O_2↑后,有的同学就随之类推出2KNO_3(?)2KN+3O_2↑这样的化学方程式。实际上KN是根本不存在的物质。这种无根无据的书写完全违背了客观事实,必须坚决杜绝。
Writing chemical equation is the high frequency test center. Many students in writing chemical equations, often appear this or that mistake. How to correctly write the chemical reaction equation? First, to respect the fact that the reaction can not be subjective and arbitrary analogy Chemical formula is a true record of chemical reactions, what substances react to generate what substances are all objective facts. Therefore, writing chemical equations must be well-founded, must not be taken as a matter of course, confused or mechanical imitation, but can not be analogized. For example, after learning 2KClO_3 (?) 2KCl + 3O_2 ↑, some students follow the similar formula of 2KNO_3 (?) 2KN + 3O_2 ↑. In fact KN is a non-existent substance. This kind of omnipotent writing totally violates the objective facts and must be resolutely put an end to it.