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  • Avogadro的号码

    A blue pickup truck parked on gravel, showing a spacious truck bed.

    Is there an easier way to load this truck?
    ::有没有一个更方便的方式 装载这辆卡车?

    When the weather is nice, many people begin to work on their yards and homes. For many projects, sand is needed as a foundation for a walk or to add to other materials. You could order up twenty million grains of sand and have people really stare at you. You could order by the pound, but that takes a lot of time weighing out. The best bet is to order by the yard, meaning a cubic yard. The loader can easily scoop up what you need and put it directly in your truck.
    ::当天气良好时,许多人开始在院子里和家里工作。 对于许多项目来说,需要沙子作为散步的基础或添加其他材料。 你可以订购2 000万颗沙粒,让人们真正盯着你看。 你可以用磅来订购,但这需要很多时间。 最好的赌注是用院子来订购, 意思是立方码的院子。 装载者可以很容易地收集你需要的东西, 直接放在卡车里。

    Avogadro’s Number
    ::阿沃加德罗的数字

    It certainly is easy to count bananas or to count elephants (as long as you stay out of their way). However, you would be counting grains of sugar from your sugar canister for a long, long time. Atoms and molecules are extremely small – far, far smaller than grains of sugar. Counting atoms or molecules is not only unwise, it is absolutely impossible. One drop of water contains about 10 22 molecules of water. If you counted 10 molecules every second for 50 years without stopping you would have counted only 1.6 × 10 10 molecules. Put another way, at that counting rate, it would take you over 30 trillion years to count the water molecules in one tiny drop.
    ::当然很容易计算香蕉或大象(只要你远离它们)。然而,你将长时间从糖罐中计算糖粒。原子和分子非常小 — — 远远小于糖粒。计算原子或分子不仅不明智,而且绝对不可能。一滴水中含有大约1022个水分子。如果你在50年中每秒计算10个分子而不停止,你就会只计算1.6×1010个分子。换句话说,以这一计算速度计算,用30万亿年的时间将水分子数成一小滴。

    Chemists needed a name that can stand for a very large number of items. Amedeo Avogadro (1776 - 1856), an Italian scientist, provided just such a number. He is responsible for the counting unit of measure called the mole . A mole (mol) is the amount of a substance that contains 6.02 × 10 23 representative particles of that substance. The mole is the SI unit for amount of a substance.  Just like the dozen and the gross, it is a name that stands for a number. There are therefore 6.02 × 10 23 water molecules in a mole of water molecules. There also would be 6.02 × 10 23 bananas in a mole of bananas, if such a huge number of bananas ever existed.
    ::化学家需要能够代表大量物品的名称。 意大利科学家Amedeo Avogadro (1776-1856) , 提供了这样的数字。 他负责计算单位的计算, 名称为内鬼。 内鬼( 摩尔) 是含有6. 02 x 1023 代表该物质的颗粒的物质的数量。 内鬼( 摩尔) 是该物质数量为6. 02 x 1023 代表质粒子的量物质。 内鬼( 摩尔) 是该物质的量量量的SI 单位。 和十多个和毛一样, 也代表一个数字。 因此, 水分子的分子分子分子分子分子中有6. 02 x 1023 水分子。 如果有如此多的香蕉存在, 香蕉的分子中也会有6. 02 x 1023 香蕉。

    Portrait of Italian scientist Amedeo Avogadro, known for defining the mole in chemistry.

    Italian scientist Amedeo Avogadro, whose work led to the concept of the mole as a counting unit in chemistry.
    ::意大利科学家阿梅德奥·阿沃加德罗(Amedeo Avogadro),其工作导致将内核作为化学计数单位的概念。

    The number 6.02 × 10 23 is called Avogadro’s number , the number of representative particles in a mole. It is an experimentally determined number. A representative particle is the smallest unit in which a substance naturally exists. For the majority of , the representative particle is the . Iron, carbon, and helium consist of iron atoms, carbon atoms, and helium atoms, respectively. Seven elements exist in nature as diatomic molecules and they are H 2 , N 2 , O 2 , F 2 , Cl 2 , Br 2 , and I 2 . The representative particle for these elements is the molecule. Likewise, all such as H 2 O and CO 2 exist as molecules and so the molecule is their representative particle.  For such as NaCl and Ca(NO 3 ) 2 , the representative particle is the formula unit . A mole of any substance contains Avogadro’s number (6.02 × 10 23 ) of representative particles.
    ::数字 6.02 × 1023 称为 Avogadro 编号, 表示摩尔内有代表性的颗粒数。 它是一个实验性确定的数字。 具有代表性的粒子是物质自然存在的最小单位。 大部分具有代表性的粒子是 . 铁、 碳 和 分别由铁原子、 碳原子 、 碳原子 和 原子 组成。 7个元素作为二亚原子分子在性质上存在, 它们是H2、 N2、 O2、 F2、 F2、 Cl2、 Br2 和 I2 。 这些元素的代表性粒子是分子。 同样, H2O 和 CO2 等所有元素都作为分子存在, 分子是其代表性的粒子。 如 NaCl 和 Ca( NO3 ) 2 , 具有代表性的粒子是公式单位。 任何物质的分子的摩尔含有有有代表性的Avogadro粒子的编号( 6.02 x 1023 )。

    A real mole on the left and a plush mole in a lab coat on the right.

    The animal mole is very different than the counting unit of the mole. Chemists nonetheless have adopted the mole as their unofficial mascot. National Mole Day is a celebration of chemistry that occurs on October 23rd (10/23) of each year.
    ::动物摩尔与内鬼的计数单位大不相同。 化学学家还是把内鬼当作他们的非官方吉祥物。 国家摩尔日是每年10月23日(10/23)的化学节日。

     

     

    Summary
    ::摘要

    • A mole of any substance contains Avogadro’s number (6.02 × 10 23 ) of representative particles.
      ::任何物质的摩尔含有Avogadro的具有代表性的颗粒号(6.02×1023)。

    Review
    ::回顾

    1. What is the SI unit for amount of a substance?
      ::物质量的SI单位是多少?
    2. What is the representative particle for an element?
      ::元素的代表性粒子是什么?
    3. The formula unit is the representative particle for what?
      ::公式单位是代表什么的粒子?