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一引言原子量是相对数值,它是一种元素的原子和另一种(我们选订的)标准元素的原子的重量比(也可说是质量比)。同时我们考虑到大多数的元素有同位素,那么原子量也就是各同位素的平均重量。的确在下文将要讨论到,由质谱方法测定原子量就是测定每一同位素的多寡和质量数,然后算成我们常用的原子量。为什么我们不用绝对数值来表示原子量呢?主要是一个原子的重量太小,没有使用的
An introduction The atomic weight is a relative value, which is the weight ratio (also can be said mass ratio) of the atom of one element and the standard element of the other (we choose). At the same time we consider that most of the elements have isotopes, then the atomic weight is the average weight of each isotope. Indeed, as will be discussed below, determining the atomic mass by mass spectrometry is a measure of the amount and mass of each isotope and is then taken as our usual atomic weight. Why do we not express the atomic weight in absolute terms? It is mainly the weight of an atom that is too small to be used