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You've probably heard of acids.
你可能听说过酸
They're sour, they're corrosive, and you really don't want them in a papercut.
他们具有酸性 腐蚀性 你绝对不会希望它们碰到你的剪纸
But inside chemistry labs, chemists also work for, they call, superacids, which are exactly what they sound like.
但在化学实验室里 化学家们也会研究所谓的超强酸 顾名思义 就是酸性超强的酸
They're incredibly corrosive and very dangerous,
它们具有强腐蚀性 非常危险
but they might also hold the keys to things like creating better plastics and fighting smogs in cities worldwide.
但它们也可能解决一些难题 例如制造更好的塑料产品以及解决世界各地的城市烟雾污染问题
Acids are molecules that easily become negatively charged,
酸是易带负电荷的分子
whether that means easily /gaining/ a negatively charged electron
意思是 容易带上负电荷
or easily /losing/ a positively charged hydrogen ion.
或者失去带正电的氢离子
And stronger acids become negatively charged more easily than weak acids.
强酸比弱酸更容易带负电荷
The pH scale is the most common way of measuring an acid's strength,
pH值是衡量酸性强弱最常用的一种方法
based on the concentration of active hydrogen ions when the acid is mixed with water.
根据 酸在水溶液中的活泼氢离子浓度进行计算
Every time the pH drops by 1, hydrogen ions are ten times more common and the acid is ten times more reactive.
pH值每减小1 氢离子浓度就变为原来的十倍 同时酸的反应活性 是原来10倍
Lemon juice, for example, has a pH of about 2,
例如 柠檬汁的pH值约为2
which means that there's one hydrogen ion donated for every hundred other molecules in the juice.
这意味着 柠檬汁中每一百个分子电离出一个氢离子
And stomach acid, with a pH of 1, gives one hydrogen ion for every ten other molecules.
pH为1的胃酸 每十个分子就电离出一个氢离子
The pH scale only really works down to 0, where there's one hydrogen ion for every molecule in the solution.
pH值测量范围最低只能到0 此时溶液中每一个分子 都能电离出一个氢离子
Below that, and for acids that aren't mixed with water,
当pH值小于0和那些未与水混合的酸
chemists use something called the Hammett acidity function,
化学家们使用 哈米特酸度函数
which is kind of a way of describing what pH a really strong acid /acts like/ it has.
来描述 这些强酸的酸性
Even if there aren't /actually/ that many hydrogen ions floating around.
即便实际上没有那么多游离氢离子
Using the Hammett acidity function, we can say that pure sulfuric acid,
根据哈密特酸度函数 纯硫酸——
a kind of acid that's used in lots of industrial processes, acts like it has a pH of -12!
一种工业过程中 经常使用的酸 其pH值相当于-12
You'll never find something as powerful as pure sulfuric acid out in nature,
你在自然界中很难找到像纯硫酸一样强的酸
since it's so strong that it violently reacts with pretty much anything it touches — including water.
它酸性强到几乎能和接触到的所有物质发生剧烈反应-包括 水
But in chemistry labs, sulfuric acid is just the beginning.
但是在化学实验室 硫酸仅仅是开始
Chemists call anything stronger than pure sulfuric acid a superacid.
化学家把一切比纯硫酸酸性更强的酸叫超强酸
Superacids were first described back in 1927 by scientists at Harvard,
在1927年哈佛科学家第一次提出超强酸概念
but superacid research really got going back in the 1960s, mainly thanks to a chemist named George Olah.
但超强酸的研究 却在19世纪60年代才有进展 这主要归功于一个名叫George Olah的化学家
Olah won the 1994 Nobel Prize in chemistry for his research into carbocations,
由于他对碳正离子的研究 Olah获得了1994年的诺贝尔化学奖
a type of molecule that has a carbon atom with a positive charge.
碳正离子是一种含碳分子带上正电荷后形成的
They're important in the production of some plastics and high-quality gasolines.
它们对于生产一些塑料及高品质汽油十分重要
Olah found that one of the best ways to make carbocations is to put organic molecules,
Olah发现制造碳正离子的最好的办法就是
which have lots of carbon, next to superacids.
将含碳有机物靠近超强酸
His discoveries make it easier for researchers to study plastic-making.
他的发现让研究制造塑料更简单
Other researchers have also found some superacids that bond really well with nitrogen oxides,
另一些研究人员还发现一些超强酸与氮氧化物结合的很好
gases made of both nitrogen and oxygen that are released in car exhaust, become smog, and lead to acid rain.
汽车排放的含氮和氧组成的尾气会造成烟雾污染 进一步形成酸雨
These scientists think they'll be able to stop nitrogen oxides before they reach the atmosphere
科学家们认为尾气排放前经过超强酸处理
by running the car exhaust past the superacid first.
能阻止氮氧化物的排放
Superacids get so strong because a lot of them are made by mixing an existing strong
一种强酸和另一种含有有超强反应活性的氟元素的酸混合
acid with another acid that involves the super-reactive element fluorine.
造就了大部分超强酸
The fluorines end up bonded to lots of hydrogen, but they'll drop the hydrogen in favor of just about anything else.
氟元素一开始与大量的氢元素结合 但是他们很快会 用其他的物质代替氢
So as soon as another molecule wanders too close, the fluorines lose all their hydrogens
因此一旦另一种分子靠的足够近 氟就会失去所有的氢
and bond with the new molecule instead -- pretty much no matter what it is.
然后去和新的分子结合——不论新分子是什么
One of the best-known superacids is one called magic acid.
最广为人知的一种超强酸是魔酸
It might sound like some kind of illegal drug cocktail,
它可能听上去像某种非法的药物混合物
but magic acid is actually used to break up lower-quality gasolines into carbocations
但其实魔酸用于 分解低质量燃油为碳正离子
so that they can form more complicated bonds and make the kind of high-quality gasoline that racecars use.
这些碳正离子能形成更为复杂的化学键 进而形成可供赛车使用的高品质燃油
Magic acid is a combination of three very strong acids, and it acts like it has a pH of -23.
魔酸由三种强酸混合而成 它的pH值相当于 -23
That's a hundred billion times more powerful than pure sulfuric acid!
比纯硫酸强上千亿倍
But it's still not the strongest superacid ever made. That honor goes to fluoroantimonic acid --
但它仍然不是已知的最强酸 最强的超强酸是氟锑酸——
a mixture of just two of the acids used to make magic acid -- which acts like it has a pH of -28.
也是由形成魔酸的两种酸 混合而成 相当于pH为-28
That's ten thousand times stronger than magic acid,
其酸性要比魔酸强一万倍
ten million billion times stronger than pure sulfuric acid,
相当于纯硫酸的亿亿倍
and a million billion trillion times stronger than concentrated hydrochloric acid —
相当于浓盐酸的千亿亿亿倍
an acid that's already strong enough to give you very severe burns.
浓盐酸已经能对你造成严重的灼伤了
So fluoroantimonic acid wouldn't just burn human skin.
所以氟锑酸不仅仅会灼伤人类的皮肤
It would eat through skin and bones and anything else it might touch --
它会腐蚀你的皮肤骨头和其他一切
and that's after it eats right through just about any container you might try to put it in
在这之前装它的容器
and almost any liquid you try to dilute it with.
和稀释的液体已经先一步被它腐蚀掉
The only way to store these sorts of substances is with teflon.
储存这类物质的唯一方法是使用聚四氟乙烯
Teflon is already made out of molecules with super-strong carbon-fluorine bonds,
聚四氟乙烯由有超强碳氟结合键的分子组成
so it won't even bow to fluoroantimonic acid.
所以它不会被氟锑酸腐蚀
No one's found a specific use for such a fantastically strong acid yet, but chemists are actively looking for one.
至今没人发现这种超强酸的具体用途 但化学家们正积极地寻找它的用途
But unless you have teflon-lined bottles lying around,
但是除非你周围全是聚四氟乙烯瓶
it's probably a good idea to just stay away from superacids.
否则你最好还是远离超强酸吧
You know what? Even if you do have teflon bottles. Just stay away.
知道么？ 哪怕你拥有聚四氟乙烯瓶 也最好远离超强酸
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感谢你观看本期的科学秀 本期内容由Patreon网站上的赞助者提供
If you want to help support this show, just go to patreon.com/scishow.
如果你想支持这个节目 登录patreon.com/sci show
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别忘了去youtube.com/scishow订阅！
