初中化学中的讨论题,往往对所要求的结果有多种,或有些结果不符合题意。然而,学生遇到这种类型的问题很容易出现漏解或错解(不符合题意的解法)。针对这种情况,笔者略举几例进行剖析,望同学们能吃透这类问题的题意。1 求某元素的化合价 例1 某元素R的氧化物的式量为m,其氯化物的式最为n。则R的化合价为_____。 解:设元素R的化合价为+x价,其原子量为y,依 The discussion questions in junior high school chemistry often have a variety of results that are required, or some results do not correspond to the questions. However, students who encounter this type of problem are prone to misunderstandings or misunderstandings (solutions that do not fit the question). In view of this situation, the author gives a few examples to analyze and hope that the students can understand this question. 1 Find the valence of a certain element Example 1 The formula of an oxide of an element R is m, and the formula of its chloride is the most n. The valence of R is _____. Solution: Let element R have a valence of +x, and its atomic weight is y.