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一、书写离子方程式的五点注意: 1.离子反应是在溶液中或熔化状态下发生的反应.凡非溶液中或非熔化状态下进行的反应一般不能写成离子方程式.亦即没有自由移动离子参加的反应,不能写离子方程式.如氢氧化钠和氯化铵固体混合加热,虽然也有离子和离子反应,但不能写成离子方程式,只能写出化学方程式,即: .再如铜和浓硫酸混合加热,虽然浓硫酸中也有H+,但浓度很小,故该反应也只能写出化学方程式.即:Cu+2H2SO4
First, note the five points of the ion equation: 1. The ionic reaction is a reaction that takes place in solution or in a molten state. Any reaction that occurs in a non-solution or non-melting state cannot generally be written as an ion equation. That is, there is no free-moving ion. Participation in the reaction, can not write the ion equation. Such as sodium hydroxide and ammonium chloride solid mixed heating, although there are ion and ion reaction, but can not be written into the ion equation, can only write out the chemical equation, namely: Copper and sulfuric acid Mixed heating, although concentrated H2SO4 also has H+, but the concentration is very small, so the reaction can only write the chemical equation. Namely: Cu+2H2SO4