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化学综合计算题的特点是情景新颖,信息量大,综合性强,是化学试题中的难题.怎样才能做好这种类型的难题呢?下面,通过实例分析,说明综合计算题的解题思路和方法.例1.过氧化钙中通常含有氧化钙和结晶水.为确定某过氧化钙的组成,进行如下实验:①称取0.270g 样品,灼热使之完全分解,生成CaO、O_2和 H_2O,得到的 O_2在标准状况下体积为33.6mL.②另取0.120g 样品,溶于稀盐酸,加热煮沸,使生成的 H_2O_2完全分解.然后,将溶液中的 Ca~(2+)完全转化
The comprehensive chemistry calculation problem is characterized by a novel situation, a large amount of information, and a comprehensive comprehensiveness. It is a problem in chemistry test questions. How can we do this type of problem? Below, examples are given to illustrate the problem-solving ideas of comprehensive calculation problems. And methods. Example 1. Calcium peroxide usually contains calcium oxide and crystal water. To determine the composition of a calcium peroxide, the following experiment was performed: 1 Weigh 0.270 g of sample, and burn it to complete decomposition, generating CaO, O 2 and H 2 O. The volume of O 2 obtained under standard conditions is 33.6 mL. 2 Another sample of 0.120 g is dissolved in dilute hydrochloric acid, heated and boiled to completely decompose the resulting H 2 O 2 . Then, the Ca 2+ in the solution is completely converted.