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  • 基基基

    Bowl with melted unsweetened chocolate and whisk, with chocolate blocks nearby.

    These blocks of baking chocolate may make your mouth water, but if you were to taste them, you would be in for an unpleasant surprise. The blocks are unsweetened chocolate. Without any added sugar, chocolate tastes bitter. Chocolate tastes bitter because it’s a base.
    ::这些烤巧克力块可能让你的嘴里有水,但是如果你尝到它们,你会感到不愉快的惊喜。 巧克力块是不加润滑的巧克力。 没有加糖,巧克力就吃苦。巧克力是苦的,因为它是碱基。

    What Are Bases?
    ::什么是"基地"号?

    Bases are that produce negative hydroxide (OH - ) when dissolved in water. An ionic compound contains positive metal ions and negative ions held together by . (Ions are atoms that have become charged particles because they have either lost or gained electrons.) An example of a base is sodium hydroxide (NaOH). When it dissolves in water, it produces negative hydroxide ions and positive sodium ions (Na + ). This can be represented by the equation:
    ::基底是水溶解时产生负氢氧化物(OH-)的基底。离子化合物含有正金属离子和负离子(Ions是原子,由于丢失或获得电子而成为有电颗粒。)一个基底的例子就是氢氧化钠(NaOH)。当其在水中溶解时,它产生负氢氧化离子和正钠离子(Na+)。这可以用公式表示:

    NaOH → H 2 O OH - + Na +

    Properties of Bases
    ::基底属性

    All bases share certain properties, including a bitter taste. ( Warning: Never taste an unknown substance to see whether it is a base!) Bases also feel slippery. Think about how slippery soap feels. That’s because it’s a base. In addition, bases conduct electricity when dissolved in water because they consist of charged particles in solution. ( Electric current is a flow of charged particles.)
    ::所有基地都有某些特性,包括苦味。 (警告:不要尝到未知物质,看它是否是基地! ) 基地也感到滑滑。 想想肥皂的滑滑感。 这是因为它是基地。 此外,基地在水溶解时进行供电,因为它们是由加热粒子溶解的。 (电流是带电粒子的流。 )

    Q: Bases are closely related to compounds called acids. How are their properties similar? How are they different?
    ::问题:碱与称为酸的化合物密切相关。它们的特性如何相似?它们有何不同?

    A: A property that is shared by bases and acids is the ability to conduct electricity when dissolved in water. Some ways bases and acids are different is that acids taste sour whereas bases taste bitter. Also, acids but not bases react with .
    ::甲:由碱和酸共有的财产是水溶解时进行电源的能力。有些方式与碱和酸不同,就是酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸盐酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸酸溶基基的电能发电。

    Detecting Bases
    ::侦察基地

    Certain compounds, called indicators, change color when bases come into contact with them, so they can be used to detect bases. An example of an indicator is a called litmus. It is placed on small strips of paper that may be red or blue. If you place a few drops of a base on a strip of red litmus paper, the paper will turn blue. You can see this in the Figure . Litmus isn’t the only detector of bases. Red cabbage juice can also detect bases, as you can see in this video .
    ::某些化合物,称为指示器,在与它们接触时会改变颜色,这样它们就可以用来探测基地。一个指示器的例子就是一个称为亮度。它被放在红色或蓝色的小纸条上。如果你在红色亮度纸条上放上几滴基点,纸就会变成蓝色。你可以在图中看到这一点。Litmus并不是唯一的基地探测器。红卷心菜果汁也可以探测基地,正如你在本视频中看到的那样。

     

     

     

     

     

    Red litmus paper turning blue when dipped in a basic solution.

    Drawing of red litmus paper turning blue in a base.
    ::红柱纸在底部变成蓝色的图画。

    Strength of Bases
    ::基数优势

    The strength of bases is measured on a scale called the scale, which ranges from 0 to 14. On this scale, a pH value of 7 indicates a neutral solution, and a pH value greater than 7 indicates a basic solution. The higher the pH value is, the stronger the base. The strongest bases, such as drain cleaner, have a pH value close to 14.
    ::基数的强度是用一个称为比例尺的尺度测量的,其范围从0到14不等。在这个尺度上,pH值为7表示中性溶液,而pH值大于7表示基本溶液。pH值越高,基数就越强。最强的基数,例如排水清洁器,其pH值接近14。

    Uses of Bases
    ::基用途

    Bases are used for a variety of purposes. For example, soaps contain bases such as potassium hydroxide (KOH). Other uses of bases can be seen in the Figure .
    ::碱用于各种用途,例如肥皂含有氢氧化钾(KOH)等碱。

    Examples of bases: soap, concrete, and deodorant, highlighting their uses.

    Summary
    ::摘要

    • Bases are ionic compounds that produce negative hydroxide ions (OH-) when dissolved in water.
      ::基底为在水溶解后产生负氢氧化离子(OH-)的离子的离子。
    • Bases taste bitter, feel slippery, and conduct electricity when dissolved in water.
      ::地底的味道苦, 感到滑, 当溶解在水中时用电。
    • Indicator compounds such as litmus can be used to detect bases. Bases turn red litmus paper blue.
      ::灯光等指示器的化合物可用于探测基地,基底变成红色灯光纸蓝色。
    • The strength of bases is measured on the pH scale. A pH value greater than 7 indicates a base, and the higher the number is, the stronger the base.
      ::基数的强度以 pH 尺度测量。 pH 值大于 7 表示基数, 数字越高, 基数越强 。
    • Bases have many important uses. For example, they are found in many cleaning products and in concrete.
      ::基地有许多重要的用途,例如,在许多清洁产品和混凝土中都有。

    Review
    ::回顾

    1. What is a base?
      ::什么是基地?
    2. What are some properties of bases?
      ::基地的一些属性是什么?
    3. How can you use litmus paper to detect a base?
      ::如何用地铁纸探测基地?
    4. Ocean water is slightly basic. What might its pH value be?
      ::海洋水略为基本,其pH值是多少?
    5. Considering the properties of bases, which of the following do you think is a base?
      1. orange juice
        ::橙汁
      2. lemonade
        ::柠檬水
      3. vinegar
        ::醋醋
      4. baking soda 
        ::苏打汽水

      ::考虑一下基地的特性, 你认为以下哪些是基地?橙汁柠檬汁醋苏打汽水。