You're familiar with this, if I had a jar of acetone or some kind of a volatile liquid, let's say I have perfume.

举个常见的例子,假如你有一瓶丙酮或者其它挥发性液体,就说香水吧

耶鲁公开课 - 生物医学工程探索课程节选

So, let's say we have an atomic number of 3, 3 that means we have 3 electrons, so we better hope to get our neutral atom that we have a charge of plus 3in the nucleus.

这也是很合理的，因为Z就是原子序数，假设原子序数是，那就有3个电子，那我们就希望,性原子有个带3个正电荷的原子核。

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