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  • General

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  • 要素要素

    Sherlock Holmes and Dr. Watson sitting in a chair during a conversation.

    Who is Sherlock Holmes?
    ::谁是夏洛克・福尔摩斯?

    The famous fictional British detective Sherlock Holmes was often said to make the statement “elementary, my dear Watson.” In reality, the closest he ever came to that line was an exchange with Watson in the short story “The Crooked Man.”  Holmes shows shrewd insight into Watson’s activities of the day. When asked how he knew what Watson was doing, Holmes simply replies “Elementary.” Regardless of exactly how he put it, Sherlock was simply referring to what the Free Dictionary defines as “relating to, or constituting the basic, essential, or fundamental part.”
    ::著名的英国虚构侦探夏洛克·福尔摩斯经常被说成是说 : “ 我亲爱的华生 ” 。 事实上,他最接近这一说法的就是在短篇小说《克鲁克人 》 ( The Crooked Man ) 中与华生的交流。 福尔摩斯对华生当天的活动表现出敏锐的洞察力。 当被问到他如何知道华生在做什么时,福尔摩斯只是回答“基本 ” 。 不管他怎么说,夏洛克只是提到自由词典所定义的“或构成基本、基本或基本部分 ” 。

    Elements
    ::要件要件要件

    An element is the simplest form of matter that has a unique set of properties. It is a pure substance that cannot be broken down into different types of substances.  As of 2010, there are 118 known elements. Ninety eight of the elements are naturally occurring on earth, while the other 20 elements have been made synthetically in a lab. The names of all the elements can be found on the periodic table . 
    ::元素是一种最简单的物质形式,具有一套独特的属性。它是一种纯物质,不能细分为不同类型的物质。截至2010年,已知元素有118个。其中98个元素在地球上自然产生,而其他20个元素是在实验室合成的。所有元素的名字可以在周期表中找到。

    Periodic table displaying 118 known elements, categorized as metals, metalloids, and nonmetals.
    The Periodic Table

    Examples of well-known elements include oxygen, iron, and gold (see the figure below). Elements cannot be broken down into a simpler substance.  Likewise, one element cannot be chemically converted into a different element.
    ::已知元素的例子包括氧、铁和黄金(见下图),不能将元素细分为更简单的物质,同样,一个元素不能化学地转换为不同的元素。

    Examples of elements: an oxygen tank, a cast iron skillet, and gold bars.
    Chemical elements are the simplest of substances. (A) An oxygen tank like this is used by people with a need for breathing assistance. (B) A simple skillet can be made from cast iron. (C) Gold bars are formed and used for monetary purposes.

    Some elements have been known for centuries (gold, silver, iron, copper, among others) while others have been created in the lab only within the last several years. Most elements do not exist as such in nature. They are so reactive that they can be found only in combination with other materials.
    ::一些元素(黄金、银、铁、铜等)几个世纪以来就已为人所知,而另一些元素仅在过去几年内才在实验室中生成。 大部分元素在性质上并不存在。 它们如此被动,只能与其他材料结合才能发现。

    Several of the elements are very valuable while others are quite inexpensive. Gold is currently worth almost $1700 per ounce. Aluminum, on the other hand, only sells for about 90 cents per pound, considerably lower than gold. Copper is worth somewhat more, selling for approximately $3.50 pound. Platinum is very valuable at about $1650 an ounce, not quite as expensive as gold.
    ::其中一些元素非常宝贵,而其他元素则相当便宜。 目前黄金每盎司价值近1700美元。 另一方面,铝每磅只卖90美分,比黄金低得多。 铜的价值略高一些,售价约为3.50英镑。 白金每盎司约1,650美元,价格不及黄金那么贵。

    There are elements all around you, including in the air you breathe. See what elements are in the air in this simulation. 
    ::您周围都有元素, 包括在您呼吸的空气中。 请看在模拟中空气中有哪些元素 。

     

     

     

    Video: The Chemical Elements Song
    ::录像:化学元素歌曲

    The Chemical Elements song, sung by Tom   Lehrer. At the time, there were only 102 elements discovered.
    ::当时只有102个元素被发现

     

     

     

    Summary
    ::摘要

    • An element is the simplest form of matter that has a unique set of properties.
      ::元素是具有一套独特属性的最简单的物质形式。
    • One element cannot be chemically converted to another element.
      ::一个元素不能化学地转换成另一个元素。

    Review
    ::回顾

    1. What is an element?
      ::什么是要素?
    2. Give the names of any two elements.
      ::给出任何两个元素的名称 。
    3. What is the name of the table that has the names of the elements?
      ::含有元素名称的表格名称是什么?
    4. How many elements are  naturally occu rr ing?
      ::有多少元素是自然发生的?