All the isotopes of a given element have the same number of protons, but differ in their number of neutrons, and hence in their atomic mass.

给定元素的所有同位素都含有相同的质子数，但它们的中子数不同，因此它们的原子质量也不同。

youdao

youdao

And, I mean literally, mass, not mole number.

我想罗嗦一下，质量，而不是摩尔数。

youdao

That is why this says atomic number, but for most intents and purposes we can say this could be atomic mass.

那就是为什么这里说原子序数，但如果没有意图和目的,我们就说是原子质量。

麻省理工公开课 - 固态化学导论课程节选

You just need a few macroscopic variables that are very familiar to you, like the pressure, the temperature, the volume, the number of moles of each component, the mass of the system.

你只需要某些你非常熟悉的宏观变量,比如压强，温度，体积，每个组分的摩尔数，系统的质量。

麻省理工公开课 - 热力学与动力学课程节选

That quantity in parenthesis, I have a mass which is a positive number. Something raised Something raised to the fourth power has got to be positive.

顺便说一句,质量这个量是个正数,四次方的值,肯定是正数。

麻省理工公开课 - 固态化学导论课程节选

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For example, an ebook that includes a self assessment or test or a way to ask a question of the author directly is a far more useful tool for the creation of more qualified leads as opposed to simply the mass number of individuals who downloaded the document.

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