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超强酸科普

The Strongest Acids in the World

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

想知道比硫酸强亿亿倍的酸吗?让我们跟着视频了解超强酸吧!魔酸和氟锑酸是怎么个组成你知道吗?

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HJF再来三碗饭

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视频来源

https://www.youtube.com/watch?v=cbN37yRV-ZY

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