TED演讲:为什么油水不能混合(2)（打印版）

　　As liquid water, these molecules are engaged in a constant and random square dance that is called the hydrogen bonding network. 作为液态水，这些分子从事着恒定而随机的被称为“氢键网络”的“方块舞”。

　　Entropy favors keeping the square dance going at all times. 熵倾向保持这种“方块舞”一直进行。

　　There are always more ways that all the water molecules can arrange in a square dance, 所有水分子被组合成“方块舞”的方式会更多，

　　as compared to if the water molecules did a line dance. 如果与水分子被组合成“排舞”方式比较的话。

　　So, the square dance constantly goes on. 因此，“方块舞”永恒地进行着。

　　So, what happens when you put salt in the water? 那么，当你把盐放进水里时会发生什么呢？

　　Well, on the molecular level, salt is actually made up of two different ions, 嗯，在分子层级上，盐其实是由两种不同的离子构成的，

　　chlorine and sodium, that are organized like a brick wall. 即氯离子和钠离子，它们就像砖墙一样被组合起来。

　　They show up to the dance as a big group in formation and sit on the side at first, 它们以编队的形式作为一个大团体出现在舞会上，并首先坐在了一边，

　　shy and a bit reluctant to break apart into individual ions to join the dance. 害羞并且有些不情愿分离成单独的离子来加入这场舞会。

　　But secretly, those shy dancers just want someone to ask them to join. 但是这些腼腆的舞者暗地里却希望有人让它们加入。

　　So, when a water randomly bumps into one of them and pulls them into the dance away from their group, they go. 所以，当一个水分子偶然碰到它们中的一个并且将它们推向舞会、远离它们的团体时，它们就会去。

　　And once they go into the dance, they don't come back out. 而且，它们只要加入了舞会，就不会再回来了。

　　And in fact, the addition of the salt ions adds more possible dance positions in the square dance, 事实上，盐的加入使得“方块舞”的组合有了更多的可能形式，

　　so it is favored for them to stay dancing with water. 所以对它们来说与水共“舞”有好处。

　　Now, let's take oil. 现在，我们来说说油。

　　With oil, the molecules are sort of interested in dancing with water, so entropy favors them joining the dance. 油分子对与水共“舞”还是有点儿兴趣的，所以熵偏向于让它们加入舞会。

　　The problem is that oil molecules are wearing gigantic ballgowns, and they're way bigger than water molecules. 但问题在于油分子都穿着巨大的长礼服，而且它们比水分子大得多。

　　So, when an oil molecule gets pulled in, their size is really disruptive to the dance 所以，当一个油分子加入舞会时，它的身量对舞会具有破坏性，

　　and the random exchange of partners that the waters engage in, a very important part of the dance. 而且水所从事的随机更换舞伴的行为是舞会的一个重要部分。

　　In addition, they are not great dancers. 此外，它们也不是杰出的舞者。

　　The water molecules try to engage the oil molecules in the dance, 水分子试图让油分子参与到舞会当中来，

　　but they just keep bumping into their dresses and taking up all the room on the dance floor. 但是它们总是碰到礼服并且占掉了舞池里的所有空间。

　　There are way more ways the waters can dance when the oil gets off the floor, 当油离开舞池时水跳舞的方式就多了许多，

　　so the waters squeeze out the oil, pushing it back to the bench with the others. 所以水把油挤了出去，把它推回到其他坐在长凳子上的油分子中。

　　Pretty soon, when a large number of oils have been squeezed over to the side, 不一会儿，当一大群油分子都被挤到一边时，

　　they band together to commiserate about how unfair the waters are being and stick together as a group. 它们就会聚到一起，并且遗憾地叹息水是多么的不公平，然后粘在一起成为一个团体。

　　So, it is this combination of the interactions between molecules 因此，就是这种分子无规则运动时，它们之间相互作用的结合方式

　　and the configurations available to them when they're moving randomly that dictates whether they mix. 以及可能实现的构造决定了它们是否能够混合。

　　In other words, water and oil don't mix because they just don't make great dance partners. 换一句话说，油和水不能混合的原因就是因为它们组不成完美的舞伴。

TED演讲:为什么油水不能混合(2)（在线收听）