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初中化学中求原子量的题目,主要有以下几种类型。1 根据原子量概念求原子量 例1.如果作为标准的碳原子质量为A千克,另一种原子的质量为B千克,则该原子的原子量是( ). (A)A/B (B)B/A (C)(12B)/A (D)(12A)/B 解 根据原子量概念,该原子的原子量为: B千克/(A千克×1/12)=(12B)/A。故应选(C)。 2 根据式量求原子量 例2.某化合物H_nRO_(2n+2)的式量为M,则R的原子量为___。 解 已知H原子量为1,氧原子量为16,设R的原子量为x,则有
There are mainly the following types of topics in the chemistry of junior high school. 1 According to the concept of atomic weight to calculate the atomic weight. 1. If the standard mass of carbon atoms is A kilograms and the mass of another atom is B kilograms, the atomic mass of the atom is (). (A) A/B (B) B/ A (C) (12B) / A (D) (12A) / B solution Based on the concept of atomic weight, the atomic weight of the atom is: B kg / (A kg × 1 / 12) = (12B) / A. Therefore, it should be selected (C). 2 Calculate the atomic weight according to the formula. Example 2. The formula of a compound H_nRO_(2n+2) is M, then the atomic weight of R is ___. Solution: It is known that H atom weight is 1, oxygen atom weight is 16, and R atom weight is x.