The difference between bonded atom and the free one in state is that the overlap of electron cloud of bonded atoms in a molecule is considered.

束缚原子不同于自由原子之处，是束缚原子考虑了在不同分子中电子云的不同重叠，将计算结果与实验及其它计算结果进行了比较。

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The fatty acids are then converted by the organisms to an aldehyde that includes a carbon atom bonded to an oxygen atom (together they create what's called a carbonyl group).

脂肪酸被生物体转化成包含碳氧双键即羰基的醛。

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Hydroxide: Any compound with one or more functional groups made up of one atom each of hydrogen and oxygen, Bonded together and acting as the hydroxide anion (OH -).

氢氧化物：包含一个或几个由一个氢原子和一个氧原子组成的官能团的化合物，氢和氧原子键合在一起以氢氧基团或氢氧阴离子(OH -)的形式起作用。

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So, in fact, yes, we did confirm that these covalent bond, at least in the case of hydrogen, we have confirmed by the numbers that we are at a lower energy state when we talk about the bonded atom versus the individual atom.

因此，事实上，是的，我们证实了共价键，至少在氢这种情况下，我们通过数据证实了,成键的原子处于能量更低的状态,当其与单个的原子相对比时。

麻省理工公开课 - 化学原理课程节选