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离子方程式的书写,是中学化学教学的重要内容之一.如何让学生准确、熟练地掌握离子方程式的书写,我认为应该做到以下几点.首先,要使学生明确离子方程式的含义,攻破书写上的难关.离子方程式是用在溶液中实际参加反应的离子的符号表示化学反应的式子.书写离子方程式可分为四个步骤,第一步,写出反应的化学方程式;第二步,把方程式两边易溶于水、易电离的物质改写成离子形式,难溶物质或难电离物质以及气体等仍以分子式表示;第三步,删去方程式两边不参加反应的离子(必要时再约去系数的公因子);第四步,检查方程式两边各元素的原子个数和离子的电荷数是否相等.
The writing of ion equation is one of the important contents of chemistry teaching in middle school.How to let students grasp the writing of ion equation accurately and skillfully, I think we should do the following: First, we should make students clarify the meaning of ion equation, Ion equation is used in the solution actually participate in the reaction of the ion symbol for the chemical reaction formula writing ionic equation can be divided into four steps, the first step, write down the reaction of the chemical equation; the second step, The equation is soluble in water, easily ionized material rewritten into ionic form, insoluble substances or difficult to ionize substances and gases are still expressed by the formula; the third step, delete the equation on both sides do not participate in the reaction of the ion (if necessary, re-about to Coefficient of the common factor); the fourth step, check the equations on both sides of each element of the number of atoms and the ion charge is equal.