放射性物质由很多不稳定原子构成。

Radioactive materials are composed of atoms that are unstable.

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不稳定原子在达到稳定状态前，需要释放出自身多余的能量，这一能量即辐射。

An unstable atom gives off its excess energy until it becomes stable. The energy emitted is radiation.

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“这些生物从一个我们从未想到的来源获取能量，”McKay惊叹，“南非的极端微生物细菌吃的是岩石里不稳定原子衰变时的放射能。”

"These creatures get their energy from sources we never imagined," McKay exclaims. "the South African extremophile bacteria are powered by the radioactive decay of unstable atoms in the rocks."

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So, if we have energy that's released, would you say that the chlorine ion is more or less stable than the chlorine atom?

那么，如果我们放出了能量，你认为氯离子比氯原子,更稳定还是更不稳定呢？

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So, that also tells us that the n minus ion is less stable than the neutral atom itself.

而且，这还告诉我们,负一价的氮离子不如中性氮原子稳定。

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