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  • General

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  • 拆散率

    A glass of iced tea with lemon slice on the rim, filled with ice cubes.

    How sweet do you like your tea?
    ::你喜欢喝多甜的茶?

    Many people enjoy a cold glass of iced tea on a hot summer day. Some like it unsweetened, while others like to put sugar in it. How fast the sugar dissolved depends on several factors: how much sugar was put in the tea and how cold it is? You usually have to stir the tea for a while to get all the sugar dissolved.
    ::许多人在炎热的夏天享受冷冰茶。有些人喜欢这种冰茶,他们不闻不问,另一些人喜欢加糖。糖溶解的速度取决于几个因素:茶里加了多少糖,它又冷又冷?你通常要先搅一下茶,才能把糖全部溶掉。

    Rate of Dissolving
    ::拆散率

    We know that the dissolving of a solid by water depends upon the collisions that occur between the solvent molecules and the particles in the solid crystal . Anything that can be done to increase the frequency of those collisions and/or to give those collisions more energy will increase the rate of dissolving. Imagine that you were trying to dissolve some sugar in a glassful of tea. A packet of granulated sugar would dissolve faster than a cube of sugar. The rate of dissolving would be increased by stirring, or agitating the solution. Finally, the sugar would dissolve faster in hot tea than it would in cold tea.
    ::我们知道用水溶解固体取决于溶剂分子和颗粒在固体晶体中发生的碰撞。任何可以增加碰撞频率和/或增加碰撞能量的措施都会提高溶解速度。想象一下你试图在一杯茶中溶解一些糖。一包颗粒糖的溶解速度会比糖的立方糖更快。溶解速度会因搅拌或促动溶解而增加。最后,糖在热茶中溶解的速度会比在冷茶中溶解的速度要快。

    Surface Area
    ::地表地区

    The rate at which a solute dissolves depends upon the size of the solute particles. Dissolving is a surface phenomenon since it depends on solvent molecules colliding with the outer surface of the solute. A given quantity of solute dissolves faster when it is ground into small particles than if it is in the form of a large chunk because more surface area is exposed. The packet of granulated sugar exposes far more surface area to the solvent and dissolves more quickly than the sugar cube.
    ::溶液溶解的速率取决于溶液颗粒的大小。溶解是一种表面现象,因为它取决于溶剂分子与溶液的外表面发生碰撞。当溶液溶解在地上变成小颗粒时,其溶液的溶解速度比由于暴露的表面面积较大而以大块的形式溶解的速度要快。颗粒糖包的表面接触溶剂的面积要大得多,溶解速度比溶液溶解的溶解速度要快。

    Agitation of the Solution
    ::解决办法的提出

    Dissolving sugar in water will occur more quickly if the water is stirred. The stirring allows fresh solvent molecules to continually be in contact with the solute. If it is not stirred, then the water right at the surface of the solute becomes saturated with dissolved sugar molecules, meaning that it is more difficult for additional solute to dissolve. The sugar cube would eventually dissolve because random motions of the water molecules would bring enough fresh solvent into contact with the sugar, but the process would take much longer. It is important to realize that neither stirring nor breaking up a solute affect the overall amount of solute that dissolves. It only affects the rate of dissolving.
    ::如果水被搅动,溶糖在水中的溶解速度会更快。 搅拌会让新鲜溶剂分子与溶液持续接触。 如果它不被搅动, 那么溶液表面的水右方就会被溶解糖分子饱和, 这意味着增加溶液更难溶解。 糖的立方体最终会溶解, 因为水分子的随机运动会带足够的新鲜溶剂与糖接触, 但这一过程需要更长的时间。 重要的是要认识到, 溶液既不能搅拌,也不得粉碎溶液会影响溶解溶液的总量。 它只会影响溶解速度 。

    Temperature
    ::温度

    Heating up the solvent gives the molecules more . The more rapid motion means that the solvent molecules collide with the solute with greater frequency and the collisions occur with more force. Both factors increase the rate at which the solute dissolves. As we will see in the next section, a temperature change not only affects the rate of dissolving, but also affects the amount of solute that dissolves.
    ::将溶剂加热会使分子更能变暖 。 越快的运动意味着溶剂分子与溶液相撞的频率越高,碰撞的强度也越强。 这两个因素都增加了溶液溶解的速度。 正如我们在下一节中看到的,温度变化不仅影响溶解的速度,而且影响溶液溶解的数量。

     

     Ever wonder how the rate of dissolving affects how much candy can  be produced? Try out this simulation and see how much candy you can make: 
    ::是否想知道溶解速度会影响多少糖果可以生产? 试一下这个模拟,看看你能生产多少糖果:

    Summary
    ::摘要

    • The rate of dissolving is influenced by surface area, stirring, and temperature.
      ::溶解速度受地表面积、扰动和温度的影响。

    Review
    ::回顾

    1. What is the relationship between surface area and rate of dissolving?
      ::地表面积和溶解率之间的关系是什么?
    2. How does stirring influence the rate of dissolving?
      ::搅拌如何影响溶解的速度?
    3. How does temperature influence the rate of dissolving?
      ::温度如何影响溶解速度?

    Explore More
    ::探索更多

    Use the resource below to answer the questions that follow. 
    ::利用以下资源回答以下问题。

     

    1. Did the sugar dissolve faster in the hot water or the cold water?
      ::糖在热水或冷水中溶解得更快吗?
    2. You wanted to perform another experiment similar to this one that would examine the relationship between the size of sugar crystal and the rate of dissolving
      1. Write a hypothesis for the experiment.
        ::为实验写一个假设
      2. Describe how you would perform the experiment.
        ::描述你将如何进行实验。

      ::您想要做另一个类似这个实验的实验, 来检查糖晶大小与解析速度之间的关系 写一个实验的假设。 描述您将如何进行实验 。