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一、利用结论开发隐含信息,进行逆向筛法在有些情境下,如果机敏地从结论(选项)入手,用逆向筛选恰好可以收到意外效果。“执因素果”与“由因导果”具有异曲同工的妙解所在。例1有X、Y、Z三种金属混合粉末,其中原子个数的比为4∶2∶1,原子量的比为3∶5∶7。将其m g溶于稀盐酸在标准状态下共放出H_23.136 L,并已知金属在化合物中均显+2价,则X、Y、Z的
First, the use of the conclusions of the development of implicit information, the reverse sieve method In some situations, if the clever start from the conclusion (option), with the reverse screening can receive unexpected results. “Cause of the result ” and “by the result of the fruit ” has similarities and differences between the wonderful solution. Example 1 has X, Y, Z three kinds of metal mixed powder, wherein the ratio of the number of atoms is 4: 2: 1, the atomic ratio of 3: 5: 7. The m g dissolved in dilute hydrochloric acid in the standard state release a total of H_23.136 L, and the metal is known in the compound were +2 valence, the X, Y, Z