Section outline

  • General

    Collapse all Expand all

  • 溶性

    Two glasses of water with sugar and salt containers beside them, illustrating solubility experiment.

    Rhonda wanted to see if salt or sugar dissolves faster in water. She added the same amount of salt and sugar to a half liter of room (20 °C) water in separate glasses. Then she stirred both mixtures. All of the sugar dissolved in less than a minute, but after 5 minutes of stirring, some of the salt still hadn’t dissolved. Even if she had kept stirring the saltwater all day, the remaining salt would not dissolve. Do you know why? The answer is their solubility.
    ::Rhonda想看看盐或糖在水中溶解的速度是否更快。 她用不同的眼镜把同样的盐和糖加到半升(20°C)的房间水中。 然后她搅拌了两种混合物。 所有的糖在不到一分钟的时间里溶解了,但经过5分钟的搅拌,有些盐还没有溶解。 即使她整天不停地搅拌盐水,剩下的盐也不会溶解。 你知道原因吗?答案是它们的溶解性。

    What Is Solubility?
    ::什么是溶解性?

    Solubility is the amount of solute that can dissolve in a given amount of solvent at a given temperature. In a solution, the solute is the substance that dissolves, and the solvent is the substance that does the dissolving. For a given solvent, some solutes have greater solubility than others. For example, sugar is much more soluble in water than is salt. But even sugar has an upper limit on how much can dissolve. In a half liter of 20 °C water, the maximum amount is 1000 grams. If you add more sugar than this, the extra sugar won’t dissolve. You can compare the solubility of sugar, salt, and some other solutes in the Table . 
    ::溶解度是溶液的量,溶液在特定温度下可以溶解一定数量的溶剂溶解。溶液是溶解的物质,溶剂是溶解的物质。对于某一溶剂来说,某些溶剂的溶解度比其他溶解度高。例如,糖在水中比盐更溶解。但是,即使是糖也有一个上限,可以溶解多少。在20°C的半升水中,最高为1000克。如果加糖更多,额外的糖就不会溶解。你可以比较表中的糖、盐和其他溶液的溶解度。

    Solute Grams of Solute that Will Dissolve in 0.5 L of Water (20 °C)
    Baking Soda 48
    Epsom salt 125
    Table salt 180
    Table sugar 1000

    Q: How much salt do you think Rhonda added to the half-liter of water in her ?
    ::问:你认为朗达在她的半升水中加了多少盐?

    A: The solubility of salt is 180 grams per half liter of water at 20 °C. If Rhonda had added less than 180 grams of salt to the half-liter of water, then all of it would have dissolved. Because some of the salt did not dissolve, she must have added more than 180 grams of salt to the water.
    ::A:在20°C时,盐的溶解度为每半升水180克。 如果Rhonda在半升水中加的盐不到180克,那么所有盐都会溶解。由于有些盐没有溶解,她一定在水中加的盐超过180克。

    Factors That Affect Solubility
    ::影响溶性的因素

    Certain factors can change the solubility of a solute. Temperature is one such factor. How temperature affects solubility depends on the state of the solute, as you can see in the Figure . 
    ::某些因素可以改变溶液的溶解性。温度就是这样的一个因素。从图中可以看出,温度如何影响溶液性取决于溶液的状态。

    Graph illustrating the relationship between temperature and solubility for solids, liquids, and gases.

    • If a solute is a or , increasing the temperature increases its solubility. For example, more sugar can dissolve in hot water than in cold water.
      ::如果溶液是溶液或溶液,温度升高会增加溶解性。 例如,在热水中溶解的糖比冷水中溶解的糖要多。
    • If a solute is a , increasing the temperature decreases its solubility. For example, less carbon dioxide can dissolve in warm water than in cold water.
      ::如果溶液是溶液,温度的升高会降低溶解性。例如,在温暖水中溶解的二氧化碳会比在冷水中溶解的二氧化碳少。

    The solubility of gases is also affected by pressure . Pressure is the force pushing against a given area. Increasing the pressure on a gas increases its solubility. Did you ever open a can of soda and notice how it fizzes out of the can? Soda contains dissolved carbon dioxide. Opening the can reduces the pressure on the gas in solution, so it is less soluble. As a result, some of the carbon dioxide comes out of solution and rushes into the air.
    ::气体的溶解性也受到压力的影响。 压力是压力对特定区域的压力。 增加气体的压力会增加其溶解性。 您有没有打开一个汽水罐, 并且注意到它是如何从罐子里飞出? Soda 含有溶解的二氧化碳。 打开它可以减少气体的溶解性压力, 从而降低溶解性。 结果, 部分二氧化碳从溶液中流出并冲入空气中。

    Q: Which do you think will fizz more when you open it, a can of warm soda or a can of cold soda?
    ::问:当你打开时,你认为哪个罐子会更丰盛, 一瓶暖苏打汽水或一瓶冷苏打水?

    A: A can of warm soda will fizz more because increasing the temperature decreases the solubility of a gas. Therefore, less carbon dioxide can remain dissolved in warm soda than in cold soda.
    ::甲:热苏打罐会因为温度的升高降低气体的溶解性而产生更多的热苏打水。 因此,与冷苏打水相比,在热苏打中可以溶解的二氧化碳更少。

    Summary
    ::摘要

    • Solubility is the amount of solute that can dissolve in a given amount of solvent at a given temperature. Some solutes have greater solubility than others.
      ::溶解度是指在特定温度下可以溶解一定数量的溶剂溶解的溶液量。有些溶液的溶解度高于其他溶解度。
    • Temperature affects the solubility of solutes in all three states. Pressure also affects the solubility of gases.
      ::温度影响三个州溶液的溶解性,压力也影响气体的溶解性。

    Review
    ::回顾

    1. What is solubility?
      ::什么是可溶性?
    2. For a given solute and solvent, what factors affect solubility?
      ::对于给定溶液和溶剂而言,哪些因素影响溶性?
    3. You open a can of room temperature soda and pour it into a glass. Why does the soda go flat? Will it go flat faster or slower if you add ice? Why?
      ::你打开一罐室温苏打水,然后倒进一个杯子里。为什么汽水是平的?如果你加冰的话,它会加速还是慢?为什么?

    Resources
    ::资源