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  • OK, today we're going to talk about the mole.

    OK,今天我們來談一下 MOLE (一字多義:莫耳、鼴鼠、痣)

  • Now, I know what you're thinking: "I know what a mole is,


  • it's a small furry creature that digs holes in the ground and destroys gardens."


  • And some of you might be thinking that it's a growth on your aunt's face with hairs sticking out of it.


  • Well, in this case, a mole is a concept that we use in chemistry to count molecules,

    但今天所講的莫耳, 是化學中的一個概念,用來計算分子、

  • atoms, just about anything extremely small.


  • Have you ever wondered how many atoms there are in the universe?


  • Or in your body? Or even in a grain of sand?


  • Scientists have wanted to answer that question,


  • but how do you count something as small as an atom?


  • Well, in 1811, someone had an idea that if you had equal volumes

    在 1811 年,有個人突發奇想,認為 如果你有相同體積

  • of gases, at the same temperature and pressure,


  • they would contain an equal number of particles.


  • His name was Lorenzo Romano Amedeo Carlo Avogadro.

    他的名字是 Lorenzo Romano Amedeo Carlo Avogadro (亞佛加厥)。

  • I wonder how long it took him to sign autographs.


  • Unfortunately for Avogadro, most scientists didn't accept the idea of the atom,


  • and there was no way to prove he was right.


  • There was no clear difference between atoms and molecules.


  • Most scientists looked at Avogadro's work as purely hypothetical,

    大多數的科學家認為 亞佛加厥的理論純綷是個假說,

  • and didn't give it much thought.


  • But it turned out he was right! By late 1860,

    但事實證明他是對的 ! 1860 年底,

  • Avogadro was proven correct, and his work helped lay the foundation


  • for the atomic theory. Unfortunately, Avogadro died in 1856.

    原子理論的基石。不幸的是,亞佛加厥死於 1856 年。

  • Now the thing is that the amount of particles in even small samples


  • is tremendous. For example,


  • If you have a balloon of any gas at zero degrees Celcius,

    假使你有一個汽球,裝進任一種氣體, 在攝氏 0 度

  • and at a pressure of one atmosphere, then you have precisely


  • six hundred and two sextillion gas particles.

    602 乘 10 的 21 次方個氣體分子。

  • That is, you have six with 23 zeros after it particles of gas in the container.

    就是 6 後面帶有 23 個 0, 這麼多個分子在裡面。

  • Or in scientific notation, 6.02 times 10 to the 23rd particles.

    或用科學記號表示為 6.02 × 10 23 個分子。

  • This example is a little misleading,


  • because gases take up a lot of space due to the high kinetic energy


  • of the gas particles, and it leaves you thinking atoms are bigger than they really are.


  • Instead, think of water molecules.


  • If you pour 18.01 grams of water into a glass,

    如果你倒入 18.01 公克的水到杯子裡,

  • which is 18.01 milliliters, which is like three and a half teaspoons of water,

    就是 18.01 毫升,大約是三個半茶匙的水,

  • you'll have 602 sextillion molecules of water.

    你就有 6.02 × 10 23 個水分子。

  • Since Lorenzo Romano - uh, never mind - Avogadro was the first one to come up with this idea,

    自從 Lorenzo Romano……嗯,算了。 亞佛加厥是第一位提出這個想法的人,

  • scientists named the number 6.02 times 10 to the 23rd after him.

    科學家用他的名字來命名 6.02 × 10 23 這個數字。

  • It is simply known as Avogadros's number.


  • Now, back to the mole. Not that mole.


  • This mole. Yep, this number has a second name.


  • The mole. Chemists use the term mole


  • to refer to the quantities that are at the magnitude of 602 sextillion.

    來表示 6.02 × 10 23 這個數量。

  • This is known as a molar quantity.


  • Atoms and molecules are so small, that chemists have bundled them into groups called moles.

    原子和分子太小了,所以化學家將它們分成一群一群, 每一群就叫做一莫耳。

  • Moles are hard for students to understand because they have a hard time


  • picturing the size of a mole,

    1 莫耳的數量,

  • or of 602 sextillion.

    或是 6.02 × 10 23。

  • It's just too big to wrap our brains around.


  • Remember our 18.01 milliliters of water?

    記得剛剛說的 18.01 毫升的水嗎?

  • Well, that's a mole of water.

    那就是 1 莫耳的水。

  • But how much is that?


  • Exactly what does 602 sextillion look like?

    6.02 × 10 23 看起來像什麼?

  • Maybe this'll help.


  • Exchange the water particles for donuts.


  • If you had a mole of donuts, they would cover the entire earth

    假如你有 1 莫耳的甜甜圈,它們可以覆蓋整個地球表面

  • to a depth of eight kilometers,

    到 8 公里高,

  • which is about five miles.

    大約是 5 英哩。

  • You really need a lot of coffee for that.


  • If you had a mole of basketballs, you could create a new planet

    如果你有 1 莫耳的籃球,你可以製造和地球

  • the size of the earth.


  • If you received a mole of pennies on the day you were born and spent a million dollars

    如果你一出生時,你有 1 莫耳的錢,你每一秒花一百萬

  • a second until the day you died at the age of 100, you would still have more than 99.99%

    直到 100 歲你死的那一天,你還有 99.99% 以上

  • of your money in the bank.


  • OK. Now we sort of have an idea how large the mole is.

    好了。現在我們大概對 1 莫耳有個概念了。

  • So how do we use it?


  • You might be surprised to know that chemists use it the same way

    你也許會驚訝化學家使用它的方法, 就如同

  • you use pounds to buy grapes, deli meat, or eggs.


  • When you go to the grocery store, you don't go to the deli counter


  • and ask for 43 slices of salami, you buy your salami by the pound.

    要 43 片臘腸,你會買幾磅的臘腸。

  • When you buy your eggs, you buy a dozen eggs.


  • When we hear the word dozen, we probably think of the number 12.

    當我們聽到「打」這個字,我們會想到數字 12。

  • We also know that a pair is two,

    我們也知道一雙就是 2,

  • a baker's dozen is 13,

    麵包師父的一打是 13,

  • a gross is 144, and a ream of paper is - anybody?

    一籮是 144,一令紙……誰知道?

  • A ream is 500.

    一令紙是 500 張。

  • Well, a mole is really the same thing.


  • For a chemist, a mole conjures up the number 6.02 times 10 to the 23rd,

    對化學家而言,1 莫耳就是 6.02 × 10 23,

  • not a fuzzy little animal. The only difference is


  • that the other quantities are more familiar to us.


  • So there you have it - the story of the mole,


  • Avogadro, basketballs, and how to buy salami at the grocery store.


OK, today we're going to talk about the mole.

OK,今天我們來談一下 MOLE (一字多義:莫耳、鼴鼠、痣)


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B2 中高級 中文 TED-Ed 分子 原子 化學家 臘腸 常數

【TED-Ed】1莫耳=6.02 X 10 **23,有多大(How big is a mole? (Not the animal, the other one.) - Daniel Dulek)

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    Why Why 發佈於 2013 年 03 月 28 日