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化学计算在中考试题中除以计算题形式出现外,还可能以选择题、填空题、实验题等形式出现。从知识点来看,化学计算主要分为:有关化学式的计算、有关化学方程式的计算、有关溶液的计算、综合计算四大类。一、有关化学式的计算主要内容:相对分子质量的计算;元素质量比计算;元素质量分数的计算;根据相对分子质量、元素的质量比或元素的质量分数,求该物质的组成、化学式、相对原子质量等。主要解题方法有公式法、方程法、关系式法、估算推理法等。命题特点:尽管化学式计算的考查的方式较为灵
Chemical calculations may appear in the form of multiple choice questions, fill in blank questions, and test questions in addition to the form of calculation questions in the mid-term examination questions. From a knowledge point of view, chemical calculations are mainly divided into four categories: calculation of chemical formulas, calculation of related chemical equations, calculation of related solutions, and comprehensive calculation. First, the calculation of the chemical formula The main content: the calculation of the relative molecular mass; the calculation of the element mass ratio; the calculation of the element mass fraction; according to the relative molecular mass, the mass ratio of the element or the mass fraction of the element, the composition, chemical formula, and relative Atomic mass, etc. The main problem solving methods are formula method, equation method, relational method, and estimation reasoning method. Proposition features: Although chemical formulas are more intensive