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化学计算是中学化学的重要内容.“一题多解”是提高化学计算教学质量的重要手段.本文拟以1988年高考一道化学计算题为例,做些探讨.[试题]甲乙两学生用加热氯酸钾的方法制取氧气.甲取了一定量的氯酸钾和0.10克二氧化锰,经混和后装入试管内加热,待收集到所需氧气时,停止加热.试管冷却后,乙称得甲留下的反应混和物的质量为4.04克,将它继续加热直至氯酸钾完全分解,收得氧气672毫升(标准状况).求甲实验时氯酸钾分解的百分
Chemical calculation is an important content of middle school chemistry.“A solution to multiple questions” is an important means to improve the teaching quality of chemistry calculation. This article plans to take a chemical calculation problem in the 1988 college entrance examination as an example to do some discussion.[Test]A and B students The method of producing oxygen by heating the method of potassium chlorate. A taking a certain amount of potassium chlorate and 0.10 g of manganese dioxide, after mixing and heating in a test tube, when the required oxygen is collected, the heating is stopped. After the test tube is cooled, B is weighed. The mass of the reaction mixture left by A was 4.04 g, and it was heated until the potassium chlorate was completely decomposed, and 672 ml of oxygen was obtained (standard condition). The percentage of decomposition of potassium chlorate during the A test was determined.