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  • If you're wondering

    如果你想知道

  • this is how the most revolutionary course in biology of all time begins.

    這就是有史以來最具革命性的生物學課程的開始。

  • Come today to learn about covalent and ionic and hydrogen bonds

    今天就來學習一下共價鍵和離子鍵以及氫鍵的知識。

  • What about electron orbitals

    那電子軌道呢

  • and the octet rule

    和八位數規則

  • and what does it all have to do with a mad man named Gilbert Lewis?

    這一切和一個叫吉爾伯特-劉易斯的瘋子有什麼關係?

  • It's all contained within.

    它'都包含在裡面。

  • Hello, I’m Hank

    你好,我是漢克

  • I assume youre here because youre interested in biology

    我想你來這裡是因為你對生物學感興趣吧?

  • and if you are, that makes sense because

    如果你是,這是有道理的,因為

  • like any good 50 Cent song, biology is just about sex and not dying.

    就像任何一首好的50美分的歌一樣,生物學只是關於性和不死。

  • Everyone watching this should be interested in sex and not dying

    大家看這個應該是對性有興趣,而不是死亡

  • being that you are, I assume, a human being.

    我想,你是一個人。

  • I'm going to be teaching this biology course differently than most courses you've ever

    我將以不同於大多數課程的方式來教授這門生物課

  • taken in your life

    生前

  • For example, I'm not going to spend the first class

    比如說,我'不打算花頭等艙

  • talking about how I’m going to spend the rest of class.

    談論我將如何度過剩下的課時。

  • I'm just going to start teaching you, like right about now.

    我'我只是要開始教你,就像現在。

  • I may say one more thing before I start teaching.

    在開始教學之前,我可以多說一句。

  • Yes, I am going to!

    是的,我要去!

  • It's that: if I’m going too fast for you, the great thing about YouTube is

    它'是:如果我對你來說太快了,YouTube最大的好處是。

  • that you can just rewind.

    你可以只是倒帶。

  • Watch stuff over and over again if it's confusing.

    看東西一遍又一遍,如果它是混亂的'。

  • Hopefully, it will become less confusing.

    希望能變得不那麼混亂。

  • And you're even allowed to fast forward through the bits that you already know.

    而且你甚至可以快進你已經知道的部分。

  • Another tip, you can actually even use the number keys on your keyboard to move around

    還有一個小竅門,其實你甚至可以用鍵盤上的數字鍵來移動。

  • in the video.

    在視頻中。

  • And I promise, you can do this to me as much as you want and I'm totally not going to mind.

    我保證,你可以盡情地對我做這個,我完全不會介意。

  • A great professor of mine once told me that in order to really understand any topic

    我的一個偉大的教授曾經告訴我,為了真正理解任何主題

  • you have to understand a little bit of the level of complexity just below that topic.

    你要了解一下這個話題下面的複雜程度。

  • The level of complexity just below biology is chemistry

    複雜程度僅次於生物學的是化學。

  • unless you're a biochemist in which case you would argue that it's biochemistry.

    除非你'是一個生物化學家,在這種情況下,你會認為它'的生物化學。

  • Either way, we're gonna have to know a little bit of chemistry in order to get through biology.

    不管是哪種方式,我們'都要懂得一點化學知識,才能通過生物學。

  • And so THAT, my friends, is where we're going to start.

    所以,我的朋友們,這就是我們要開始的地方'。

  • I am a collection of organic molecules called Hank Green.

    我是一個有機分子的集合體,叫漢克-格林。

  • Organic compounds are a class of compounds that contain carbon.

    有機化合物是一類含碳的化合物。

  • And carbon is this sexy little minx on the periodic table

    而碳是元素週期表上這個性感的小東西

  • that's, you know...

    那是,你知道... ...

  • disinterested in monogamy.

    對一夫一妻制不感興趣。

  • A jezebel. Bit of a tramp. Hussy.

    一個Jezebel。位的流浪漢。婊子。

  • When I say carbon is small I mean that it's actually

    當我說碳是小的時候,我的意思是它實際上是

  • as an atom, it's a relatively small atom.

    作為一個原子,它是一個比較小的原子。

  • It has 6 protons and 6 neutrons for a total atomic weight of 12.

    它有6個質子和6箇中子,總原子量為12。

  • Because of that, carbon doesn't take up a lot of space.

    正因為如此,碳不會佔用很多空間。

  • And so carbon can form itself into weird rings, and sheets and spirals

    所以碳可以形成奇怪的環、片和螺旋狀的東西

  • and double and even triple bonds.

    和雙倍甚至三倍的債券。

  • It can do all sorts of things that could never be accomplished by more bulky atoms.

    它可以做各種更笨重的原子所無法完成的事情。

  • It's basically, your atomic equivalent of an olympic gymnast.

    它基本上,你的原子相當於奧運體操運動員。

  • It can only do all of those wonderful, beautiful, elegant things because it's kind of tiny.

    它只能做到所有這些美妙、美麗、優雅的事情,因為它'的那種微小。

  • It's also said that carbon is kind

    也有人說,碳是一種。

  • and that's an interesting sort of thing to say about an atom.

    這對原子來說是件很有趣的事情。

  • It's not like some other elements that are just

    它不像其他一些元素,只是。

  • desperately trying to do anything they can

    竭盡全力

  • to fill up their electron orbitals.

    以填補其電子軌道。

  • No, carbon knows what it's like to be alone, and so it's not all

    不,碳知道孤獨的感覺,所以並不是所有的人都知道

  • Please! I'll do anything for your electrons!”

    "求求你了!我願意為你的電子做任何事情!"

  • needy like fluorine or chlorine or sodium is.

    像氟或氯或鈉一樣需要。

  • Elements like chlorine if you breath them in they like literally tear up your insides

    像氯這樣的元素,如果你把它們吸入體內,它們就會把你的內臟撕碎。

  • and sodium, sodium is insane if you put it in water it explodes!

    和鈉,鈉是瘋狂的如果你把它放在水裡就會爆炸!

  • Carbon though...

    碳雖然...

  • Meh.

    呵。

  • It wants more electrons, but it's not gonna kill to get them.

    它想要更多的電子,但它不會為了得到電子而殺人。

  • It makes and breaks bonds like a 13-year old mall rat.

    它像13年的商場老鼠一樣製造和破壞債券。

  • And it doesn't even hold a grudge.

    而且它甚至不記仇。

  • Carbon is also, as I mentioned before, a bit of a tramp, because, it needs four extra electrons

    正如我之前提到的,碳也是一個有點流浪的東西,因為,它需要額外的四個電子。

  • and so it'll bond with pretty much whoever happens to be nearby

    所以它會與幾乎所有碰巧在附近的人建立聯繫。

  • And also because it needs four electrons, it'll bond with two, or three

    也因為它需要4個電子,所以它會和兩個,或者三個電子結合在一起。

  • or even four of those things at the same time

    乃至四種以上

  • And carbon is willing and interested to bond with lots of different molecules

    而碳是願意並有興趣與很多不同的分子結合的。

  • like hydrogen, oxygen, phosphorous, nitrogen

    如氫、氧、磷、氮

  • or to other molecules of carbon.

    或對其他碳分子。

  • It can do this in infinite configurations

    它可以在無限的配置中做到這一點

  • allowing it to be the core atom of complicated structures that make living things like ourselves

    讓它成為複雜結構的核心原子,使我們這樣的生物得以生存

  • because carbon is this perfect mix of small, kind, and a little bit trampy

    因為碳是這個完美的組合 小巧,善良,和一點點躑躅不前。

  • life is entirely based on this element.

    生活完全是基於這個因素。

  • Carbon is the foundation of biology.

    碳是生物的基礎。

  • It's so fundamental that scientists have a pretty difficult time

    它是如此的基本,以至於科學家們相當困難。

  • even conceiving of life that isn't based on carbon.

    甚至設想生命是不是基於碳。

  • Life is only possible on earth because carbon is always floating around in our atmosphere

    只有地球上的生命才有可能,因為碳總是漂浮在我們的大氣層中。

  • in the form of carbon dioxide.

    以二氧化碳的形式存在。

  • So it's important to note, when I talk about carbon bonding with other elements

    所以要注意的是,當我說到碳與其他元素的結合時,很重要的一點是

  • I'm not actually talking about sex, it's just a useful analogy.

    我'其實不是在說性,這只是一個有用的比喻。

  • Carbon, on it's own, is an atom with 6 protons, 6 neutrons, and 6 electrons.

    碳,就其本身而言,是一個有6個質子、6箇中子和6個電子的原子。

  • Atoms, have electron shells, and they need to have these shells filled

    原子,有電子殼,它們需要有這些電子殼的填充。

  • in order to be happy, fulfilled atoms.

    才能成為快樂、滿足的原子。

  • So carbon, has 6 total electrons, 2 for the first shell

    所以碳,共有6個電子,其中2個是第一殼的電子

  • so it's totally happy

    所以它完全快樂

  • and 4 of the 8 it needs to fill the second shell.

    和8箇中的4個,它需要填補第二個殼。

  • Carbon forms a type of bond that we call covalent.

    碳形成的一種鍵,我們稱之為共價鍵。

  • This is when atoms actually are sharing electrons with each other.

    這時,原子之間實際上是在互相分享電子。

  • So in the case of methane, which is pretty much the simplest carbon compound ever.

    所以在甲烷的情況下,這幾乎是有史以來最簡單的碳化合物。

  • Carbon is sharing it's 4 electrons, in it's outer electron shell, with 4 atoms of hydrogen.

    碳是分享它的4個電子,在它'的外層電子殼,與4個氫原子。

  • Hydrogen atoms only have 1 electron, so they want their first S orbital filled.

    氫原子只有1個電子,所以它們希望自己的第一個S軌道被填滿。

  • Carbon shares its 4 electrons with those 4 hydrogens

    碳與這4個氫共享4個電子。

  • and those 4 hydrogens each share 1 electron with carbon.

    而這4個氫與碳各共享1個電子。

  • So everybody's happy.

    所以大家都很高興。

  • In chemistry and biology this is often represented by what we call Lewis dot structures.

    在化學和生物學中,這通常用我們所說的劉易斯點結構來表示。

  • Good lord, I'm in a chair!

    天啊,我坐在椅子上了!

  • I'm in a chair and there's a book.

    我'在椅子上,有'的書。

  • Apparently I have something to tell you that's in this book.

    顯然,我有話要告訴你,'在這本書裡。

  • Which is a book called Lewis: Acids and Bases.

    這是一本叫劉易斯的書。酸和鹼。

  • By Hank Green

    作者:漢克-格林

  • Gilbert Lewis, the guy who thought up Lewis dot structures

    吉爾伯特-劉易斯,想出劉易斯點陣結構的人

  • was also the guy behind Lewis Acids and Bases

    也是劉易斯酸和鹼的幕後推手。

  • and he was nominated for the nobel prize

    他被提名為諾貝爾獎得主

  • 35 times.

    35次。

  • This is more nominations than anyone else ever in history.

    這比歷史上任何一個人的提名都多。

  • And the number of times he won was roughly the same number of times

    而他獲勝的次數也大致相同。

  • that everyone else in the world has won.

    世界上其他所有人都贏了。

  • Which is zero.

    也就是零。

  • Lewis disliked this a great deal.

    劉易斯很不喜歡這個。

  • It's kind of like a baseball player having more hits than any other player in history

    這有點像棒球運動員比歷史上任何其他球員擁有更多的命中率。

  • and no home runs.

    而沒有全壘打。

  • He may have been the most influential chemist of all time.

    他可能是有史以來最有影響力的化學家。

  • He coined the term photon, he revolutionized how we think about acids and bases

    他創造了光子一詞,他徹底改變了我們對酸和鹼的看法

  • and he produced the first molecule of heavy water.

    並且他產生了第一個重水分子。

  • He was the first person to conceptualize the covalent bond that we're talking about right

    他是第一個概念化我們正在談論的共價鍵的人。

  • now.

    現在。

  • Gilbert Lewis died alone in his laboratory while working on cyanide compounds

    吉爾伯特-劉易斯在研究氰化物時,獨自一人死在實驗室裡。

  • after having had lunch with a younger, more charismatic colleague

    和一個更年輕、更有魅力的同事吃過午飯後

  • who had won the Nobel Prize and who had worked on the Manhattan project.

    曾獲得諾貝爾獎,曾參與曼哈頓項目的。

  • Many suspect that he killed himself with the cyanide compounds he was working on

    很多人懷疑他是用他正在研究的氰化物自殺的。

  • but the medical examiner said heart attack, without really looking into it.

    但法醫卻說是心臟病,沒有真正查清楚。

  • I told you all of that because

    我告訴你這些是因為

  • the little Lewis dot structure that we use to represent how atoms bond to each other

    劉易斯小點結構

  • is something that was created by a troubled mad genius.

    是一個麻煩的瘋狂天才所創造的東西。

  • It's not some abstract scientific thing that's always existed.

    它'不是什麼抽象的科學的東西,'一直存在。

  • It's a tool that was thought up by a guy

    這是一個人想出來的工具。

  • and it was so useful that we've been using it ever since.

    而且它是如此有用,我們'一直在使用它,因為。

  • In biology most compounds can be displayed in Lewis dot structure form

    在生物學中,大多數化合物都能以劉易斯點結構形式顯示出來

  • and here's how that works:

    和這裡'的如何工作。

  • These structures basically show how atoms bond together to make up molecules.

    這些結構基本上顯示了原子是如何結合在一起組成分子的。

  • And one of the rules of thumb when you're making these diagrams

    當你做這些圖的時候,有一個經驗法則就是

  • is that the elements that we're working with here react with one another in such a way

    是,我們在這裡工作的元素彼此之間的反應,以這樣的方式。

  • that each atom ends up with 8 electrons in it's outermost shell.

    每個原子最後都有8個電子在它'的最外層。

  • That is called the Octet Rule.

    這就是所謂的八分法則。

  • Because atoms want to complete their octets of electrons to be happy and satisfied.

    因為原子要完成自己的八次電子,才會快樂和滿足。

  • Oxygen has 6 electrons in it's octet and needs 2 which is why we get H2O

    氧氣有6個電子,需要2個,這就是為什麼我們會得到H2O。

  • It can also bond with carbon

    它也可以與碳結合

  • which needs 4.

    其中需要4。

  • So you get 2 double bonds to 2 different oxygen atoms and you end up with CO2.

    所以你得到2個雙鍵到2個不同的氧原子上,最後就得到了二氧化碳。

  • That pesky global warming gas and also the stuff that makes all life on Earth possible.

    那討厭的全球變暖氣體,也是讓地球上所有生命得以存在的東西。

  • Nitrogen has 5 electrons in its outer shell. Here's how we count them:

    氮的外殼有5個電子。這裡'是我們如何計算它們。

  • There are 4 placeholders. Each of them wants 2 atoms.

    有4個佔位符。他們每個人都想要2個原子。

  • And like people getting on a bus they prefer to start out not sitting next to each other.

    而像人們上公車一樣,他們更願意一開始就不挨著坐。

  • I'm not kidding about this, they really don't double up until they have to.

    我'不是在開玩笑,他們真的是不到萬不得已不會加倍。

  • So for maximum happiness, nitrogen bonds with 3 hydrogens, forming ammonia.

    所以要想獲得最大的幸福感,氮與3個氫結合,形成氨。

  • Or with 2 hydrogens sticking off another group of atoms, which we call an amino group.

    或者用2個氫從另一組原子上粘下來,我們稱之為氨基。

  • And if that amino group is bonded to a carbon that is bonded to a carboxylic acid group

    如果該氨基基團與與羧酸基團結合的碳結合在一起

  • then you have

    那麼你就

  • an amino acid!

    氨基酸!

  • You've heard of those, right?

    你聽說過這些,對嗎?

  • Sometimes electrons are shared equally within a covalent bond like with O2.

    有時電子在共價鍵內是平等共享的,比如O2。

  • That's called a non-polar covalent bond. But often one of the participants is more greedy.

    這就叫非極性共價鍵。但往往其中一個參與者比較貪心。

  • In water for example, the oxygen molecule sucks the electrons in

    例如,在水裡,氧分子會把電子吸進去。

  • and they spend more time with the oxygen than with the hydrogens.

    他們花更多的時間與氧比與氫。

  • This creates a slight positive charge around the hydrogens

    這將在氫的周圍產生輕微的正電荷。

  • and a slight negative charge around the oxygen.

    和氧氣周圍的輕微負電荷。

  • When something has a charge we say that it's polar. It has a positive and negative pole.

    當一個東西有電荷時,我們說它是極性的。它有一個正極和負極。

  • And so it's a polar covalent bond.

    所以它'是一個極性的共價鍵。

  • Now let's talk for a moment about a completely different type of bond, which is an ionic

    現在讓我們來談一談一種完全不同的鍵,即離子型的鍵

  • bond.

    債券。

  • And that's when, instead of sharing electrons

    這時,不是共享電子,而是分享電子。

  • atoms just completely wholeheartedly donate or accept an electron from another atom

    原子全心全意地捐贈或接受另一個原子的電子

  • and then live happily as a charged atom.

    然後作為一個帶電的原子快樂地生活。

  • And there is actually no such thing as a charged atom.

    而實際上並不存在帶電原子這種東西。

  • If an atom has a charge, it's an ion.

    如果一個原子有電荷,它就是一個離子。

  • Atoms in general prefer to be neutral, but compared with having a full octet, it's not

    原子一般都喜歡中性,但與有一個完整的八位數相比,它'不

  • that big of a deal.

    這麼大的交易。

  • Just like we often choose between being emotionally balanced and sexually satisfied

    就像我們經常會在情感平衡和性滿足之間選擇

  • atoms will sometimes make sacrifices for that octet.

    原子有時會為了這個八位數做出犧牲。

  • The most common ionic compound in our daily lives is salt.

    我們日常生活中最常見的離子化合物是鹽。

  • Sodium chloride. NaCl.

    氯化鈉。氯化鈉。

  • The stuff, despite it's deliciousness, as I mentioned previously

    這東西,儘管它'的美味,正如我之前提到的

  • is made up of two really nasty chemicals. Sodium and chlorine.

    是由兩種非常討厭的化學物質組成的。鈉和氯。

  • Chlorine is what we call a halogen, which is an element that only needs one electron

    氯就是我們所說的鹵素,它是一種只需要一個電子的元素。

  • to fulfill it's octet.

    來履行它'的八字訣。

  • And sodium is an alkaline metal which means that it only has one electron in it's octet.

    而鈉是一種鹼性金屬,這意味著它的八元組中只有一個電子。

  • So chlorine and sodium are so close to being satisfied

    所以氯和鈉就差一點就滿足了。

  • that they will happily destroy anything in their path in order to fulfill their octet.

    他們為了實現他們的八字方針,會很樂意地摧毀任何擋在他們面前的東西。

  • And thus, there's actually no better outcome than just to get

    是以,其實沒有什麼更好的結果,只是為了得到'。

  • chlorine and sodium together and have them lovin' on each other.

    氯和鈉在一起,讓他們互相愛護'。

  • They immediately transfer their electrons.

    它們立即轉移電子。

  • So that sodium doesn't have it's one extra, and chlorine fills it's octet.

    這樣,鈉就沒有它'多了一個,而氯就填滿了它'的八位數。

  • They become Na+ and Cl- and are so charged that they stick together

    它們變成Na+和Cl-,並帶電,以至於它們粘在一起。

  • and we call that stickiness an ionic bond.

    我們把這種粘性稱為離子鍵。

  • And just like if you have two really crazy friends

    就像如果你有兩個非常瘋狂的朋友一樣。

  • it might be good to get them together so that they'll stop bothering you.

    也許是好的,讓他們在一起,這樣他們'就不會再打擾你了。

  • Same thing works with sodium and chlorine.

    鈉和氯也是一樣的道理。

  • You get those two together, and they'll bother no one.

    你把這兩個人放在一起,他們'就不會打擾任何人。

  • And suddenly, they don't want to destroy, they just want to be delicious.

    突然間,他們不想破壞,只想成為美味。

  • Chemical changes like this are a big deal.

    這樣的化學變化是個大問題。

  • Remember, chlorine and sodium, just a second ago, were definitely killing you, and now

    記住,氯和鈉,就在一秒鐘前,絕對是要你的命,而現在

  • they're tasty.

    他們'好吃。

  • Now we're coming to the last bond that we're going to discuss

    現在我們要討論的是最後一個債券的問題了

  • in our intro to chemistry here and that's the hydrogen bond.

    在我們的化學介紹這裡,那'是氫鍵。

  • Imagine that you remember water, I hope that you didn't forget water.

    想象一下,你還記得水,我希望你沒有'忘記水。

  • Since water is stuck together in a polar covalent bond

    由於水是以極性共價鍵粘在一起的

  • the hydrogen bit is positively charge and the oxygen bit is negatively charged.

    氫位帶正電,氧位帶負電。

  • So when water molecules are moving around

    所以當水分子在周圍移動時

  • we generally think of them as a perfect fluid but they actually stick together a little

    我們通常認為它們是完美的液體,但實際上它們是有點粘在一起的。

  • bit.

    位。

  • Hydrogen side to oxygen side.

    氫側對氧側。

  • You can actually see this with your eyes if you fill up a glass of water too full

    如果你把一杯水灌得太滿,其實你可以用眼睛看出來的

  • it will bubble at the top. The water will stick together at the top.

    它的頂部會有氣泡。水會在頂部粘在一起。

  • That's the polar covalent bonds sticking the water molecules to each other

    那是極性共價鍵,將水分子粘在一起

  • so that they don't flow right over the top of the glass.

    以便它們不會直接流過玻璃的頂部。

  • These relatively weak hydrogen bonds happen in all sorts of chemical compounds

    這些相對較弱的氫鍵發生在各種化合物中。

  • they don't just happen in water. An they actually play an extremely important role in proteins

    他們不只是發生在水中。它們實際上在蛋白質中起著極其重要的作用。

  • which are the chemicals that pretty much up our entire bodies.

    這些化學物質幾乎佔據了我們整個身體。

  • A final thing to note here is that bonds, even covalent bonds, ionic bonds

    這裡最後要注意的是,鍵,甚至是共價鍵、離子鍵

  • even with their own class

    連同自己的班級

  • are often much different strengths.

    往往是實力大不相同。

  • And we tend to just write them with a little line

    而我們往往只是寫他們與一個小行。

  • but that line can represent a very very strong covalent bond or a relatively weak covalent

    但這條線可以代表非常非常強的共價鍵,也可以代表相對較弱的共價鍵。

  • bond.

    債券。

  • Sometimes ionic bonds are stronger than covalent bonds

    有時,離子鍵比共價鍵更強。

  • though that's generally not the case and the strength of covalent bonds varies wildly.

    雖然一般情況下不是這樣,共價鍵的強度也大不相同。

  • How these bonds are made and broken is intensely important to life.

    這些紐帶如何產生和斷裂,對生命有著強烈的重要性。

  • And to our lives. Making and breaking bonds is in fact the key to life itself

    而對於我們的生活。建立和打破紐帶其實是生命本身的關鍵。

  • and also the key to death. For example, if you were to ingest some sodium metal.

    也是死亡的關鍵。比如說,如果你攝入一些金屬鈉。

  • Keep this in mind as we move forward through biology:

    在我們學習生物的過程中,要牢記這一點。

  • Even the sexiest person you have ever met in your life

    即使是你一生中見過的最性感的人也不例外

  • is just a collection of organic compounds rambling around in a sack of water.

    就是一袋水裡漫無邊際的有機化合物的集合。

  • Review time!

    複習時間!

  • Now we have the table of contents

    現在我們有了目錄

  • Which I know is supposed to come at the beginning of things

    我知道這應該是事情的開始

  • But we are revolutionary here we're doing it different

    但我們是革命性的,我們在做不同的事情。

  • so you can click on any of the things here

    所以你可以點擊這裡的任何東西

  • and you can go back and review what you learned.

    你可以回去複習你所學的知識。

  • Or didn't learn.

    或者沒有'學。

  • And if you have questions please please please please please please please

    如果你有問題,請你請你請你請你請你請你請你。

  • ask them in the comments and we'll be down there answering them for you.

    在評論中問他們,我們'會在下面為你解答。

  • So