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有关化学式的计算,是初中化学计算的难点,也是中考命题的热点。同学们在解有关化学式的习题时,若能根据题给信息进行巧妙转换,可化隐为显,化难为易。达到简洁、准确的解题目的。现以近年中考题为例介绍几种转换化学式的常用技巧。1 放大 例1 在NO、NO_2、N_2O、N_2O_3、N_2O_5中,与等质量的氮元素相结合的氧元素的质量比为__。 解析:将五种化学式进行放大转变为“N_2O_n”型,即为N_2O_2、N_2O_4、N_2O、N_2O_3、N_2O_5,显然氧元素的质
The calculation of the chemical formula is a difficult point in the chemical calculation of junior high school and is also a hot topic in the examination topic. When classmates solve problems related to chemical formulas, if they can make ingenious conversions based on the information they give, they can make it obvious and it is difficult to change. To achieve a simple and accurate solution to the problem. In recent years, as an example, several common techniques for converting chemical formulas have been introduced. 1 Amplification Example 1 In NO, NO 2 , N 2 O, N 2 O 3 , and N 2 O 5 , the mass ratio of the oxygen element combined with an equal mass of nitrogen is __. Analytical: The five chemical formulae are converted into “N_2O_n” type, namely N_2O_2, N_2O_4, N_2O, N_2O_3, N_2O_5, apparently the quality of oxygen