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  • Acids and bases are everywhere.

    酸與堿無處不在。

  • They're used to make foods,

    它們被用來製作食物,

  • soaps and detergents,

    香皂和清潔劑,

  • fertilizers,

    化肥,

  • explosives,

    炸藥,

  • dyes,

    染料,

  • plastics,

    塑膠,

  • pesticides,

    農藥,

  • even paper.

    還有紙。

  • Our stomachs are very acidic.

    我們的胃裡是強酸性的。

  • Our blood is slightly basic.

    我們的血液是呈弱鹼的。

  • Our proteins are made up of amino acids,

    我們的蛋白質是由氨基酸組成的,

  • and the letters in our genetic code,

    還有那些遺傳密碼中的字母,

  • those As, Ts, Cs, and Gs,

    As,Ts, Cs, 和 Gs,

  • are all bases.

    都是堿。

  • You were probably taught

    你可能學過

  • how acids and bases behave

    分子級的酸和堿

  • on the molecular level.

    如何作用。

  • You were probably never taught

    你可能從不知道

  • that a long time ago,

    很久以前,

  • like ancient Greek ago,

    比古希臘還往前,

  • before anyone knew about atoms or molecules,

    在沒有人知道原子或分子時,

  • acids and bases were defined

    酸和堿已經因它們的

  • by how they behaved.

    作用表現而有定義。

  • Acids tasted sour and corroded metal.

    酸嘗起來是酸的,還腐蝕金屬。

  • Bases felt slippery

    堿觸感滑

  • and could somehow counteract acids.

    還能一定程度上抵消酸的作用。

  • When molecules dissolved in water interact,

    當在水中溶解的分子相互作用,

  • they are exchanging two main currencies

    它們與周圍的物質交換

  • with their surroundings:

    兩個主要流通物

  • protons, also known as hydrogen ions,

    質子,也就是氫離子,

  • and electrons.

    以及電子。

  • Depending on how a molecule is composed or shaped,

    取決於分子的組成和形狀,

  • it may be willing to donate or accept

    在這個群體中,它與其他的成員之間

  • either protons or electrons

    可能願意釋放,或者接受

  • with some other community member.

    質子或電子。

  • And some molecules are far more aggressive than others

    有些分子在釋放或接受任一流通物時

  • when it comes to donating or accepting either currency.

    比其他分子強悍許多。

  • Remember that protons are positively charged

    切記質子是帶正電荷的

  • and electrons are negatively charged.

    電子是帶負電荷的。

  • So, if a molecule is willing to give up a proton,

    所以,如果一個分子要釋放一個質子,

  • that's not too different

    和接收一個電子

  • from it being willing to accept an electron --

    不會有什麼大的差異

  • either way it's becoming more negatively charged.

    任何一種方式都只會讓它帶更多負電荷。

  • Other molecules are willing to accept a proton

    其它分子想要接收質子

  • or give up an electron.

    或釋放一個電子。

  • These are becoming more positively charged.

    這些就變得帶有更多正電荷。

  • Some substances are so aggressive

    一些物質在釋放它們的質子時

  • about donating their protons

    表現得十分強勢,

  • that when they get a chance,

    一旦得到機會,

  • all of the molecules in a sample

    樣本中所有的分子都會

  • will dump a proton,

    釋放出一個質子,

  • sometimes more than one,

    有時是多個

  • to the surrounding water molecules.

    至周圍的水分子中。

  • We call these strong acids.

    我們稱這些為強酸。

  • Meanwhile, some compounds are so ready

    同時,一些化合物迫不及待

  • to accept a proton

    需要一個質子,

  • that they won't wait around,

    它們不會傻等,

  • they'll just rip one off water,

    而是直接從有兩個質子的水分子

  • which usually has two protons

    中搶一個過來,

  • but is generous enough to hang out with just one.

    但水分子很大方,剩一個質子也行。

  • We call these strong bases.

    我們把這些叫做強鹼。

  • Other acids and bases are not so strong.

    其它的酸和堿沒有那麼強。

  • They may donate just a few of their protons to water

    它們可以往水中釋放少量質子

  • or accept just a few protons from water,

    或從水中接受少量質子,

  • but most of their molecules stay exactly the same.

    但是它們的大多數分子都保持不變。

  • If left alone in water,

    如果被單獨置於水中,

  • they'll reach some equilibrium point

    在百分之一或

  • where maybe only one out of a hundred

    萬分之一的分子

  • or one out of ten thousand of their molecules

    與水交互流通時

  • has exchanged currency with water.

    達到某個平衡點

  • As you might guess,

    你可能猜測,

  • we label these acids and bases weak,

    我們把這些酸和堿標記為做弱酸,弱鹼,

  • but in the common sense of the word,

    但是常識中,

  • they're not weak.

    它們不弱。

  • The vinegar in your salad dressing

    你的沙拉調味的醋

  • that you can smell from across the room,

    的味道你能在整個房間裡聞到,

  • that is a weak acid.

    它是弱酸。

  • The ammonia you spray on glass

    氨水噴在玻璃上

  • for a streak-free shine,

    讓玻璃晶瑩剔透,

  • that is a weak base.

    那是弱鹼。

  • So, it doesn't take much to be an active player

    所以,在化學的經濟體系裡,

  • in the chemical economy.

    不必投入太多也能成為活躍玩家。

  • Most acid-base chemistry takes place in water,

    大多數的酸鹼化學過程都發生在水中,

  • which can act as either an acid or a base,

    水像一個24小時分子ATM,

  • accepting deposits and enabling withdrawals

    通過”吸納存款“和”授權取款“

  • like a 24-hour molecular ATM.

    起到酸或堿的作用。

  • And when a proton-deposit customer,

    但一個客戶存入質子,

  • that's an acid,

    它就是酸,

  • and a proton-withdrawal customer,

    當一個客戶提取質子,

  • the base,

    它是堿,

  • shop at the same time,

    當他們同時購物

  • their net effect on water's account

    他們在水中的有效效應

  • may cancel out,

    會抵消,

  • and we call this neutralization.

    我們把這個叫做中和作用。

  • Now, certain molecules can behave

    現在,一些分子不必融水

  • as acids or bases without water,

    就可以起到酸和堿的作用,

  • but that's another story.

    但那就是另一回事了。

  • Let's end by saluting water

    最後,我們向水致敬

  • as the resilient and fair banker

    因為它平衡酸和堿

  • for acids and bases.

    公平的銀行家。

  • It's always open for business,

    它總對商家開放,

  • doesn't charge interest,

    也不收利息,

  • and will never foreclose on your molecules,

    並且永遠不會阻止你贖回你的分子,

  • which is more than I can say for [bleep].

    酷斃了。

  • Waah-waah.

    哇-哇

Acids and bases are everywhere.

酸與堿無處不在。

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B2 中高級 中文 美國腔 TED-Ed 質子 分子 釋放 作用 電子

【TED-Ed】酸和鹼的優點和缺點 (The strengths and weaknesses of acids and bases - George Zaidan and Charles Morton)

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    Kevin Tan 發佈於 2014 年 09 月 11 日
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