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  • 液溶解

    Aerial view of an oil spill in the Gulf of Mexico, showing slicks on the water's surface.

    Does oil dissolve in water?
    ::石油在水中溶解吗?

    In 2010, a major oil spill occurred when an explosion on a drilling rig in the Gulf of Mexico released millions of gallons of crude oil into the Gulf.  Oil is primarily a of ( organic compounds composed of only carbon and hydrogen atoms). Because of its composition, oil does not dissolve in water.  As a result, much of the Gulf of Mexico was contaminated, as was a great deal of shoreline in the affected area.
    ::2010年,墨西哥湾的钻井平台爆炸将数百万加仑原油释放到海湾时发生了重大石油泄漏事件,石油主要是(由碳和氢原子组成的有机化合物),石油的成分不会在水中溶解,因此墨西哥湾大部分地区受到污染,受影响地区的许多海岸线也受到污染。

    Liquid-Liquid Solutions
    ::液-液溶解

    Nonpolar compounds do not dissolve in water.  The attractive forces that operate between the particles in a nonpolar are weak dispersion forces.  However, the nonpolar molecules are more attracted to themselves than they are to the polar water molecules.  When a nonpolar such as oil is mixed with water, two separate layers form because the liquids will not dissolve into each other ( Figure ).  When another polar liquid such as ethanol is mixed with water, they completely blend and dissolve into one another.  Liquids that dissolve in one another in all proportions are said to be miscible .  Liquids that do not dissolve in one another are called immiscible .  The general rule for deciding if one substance is capable of dissolving another is “like dissolves like.”  A nonpolar solid such as iodine will dissolve in nonpolar lighter fluid , but will not dissolve in polar water.
    ::非极化化合物不会在水中溶解。在非极化颗粒之间运行的诱人力量是微弱的分散力量。然而,非极化分子比极化水分子更吸引自己。当石油等非极化分子与水混合时,由于液体不会溶解而形成两个不同的层(图 ) 。 当乙醇等另一种极性液体与水混合时,它们完全混合并溶解为一体。据说,在各种程度上相互溶解的液体是被误导的。不溶于彼此的液体被称为不溶液。决定一种物质能否溶解另一个物质的一般规则是“像溶解一样的 ” 。 一种非极化的固体,如碘,将溶解于非极化的液体,但不会溶于极化的水中。

    A glass showing distinct layers of water and nonpolar oil, illustrating immiscibility.

    Water and oil form separate layers when they are mixed because the nonpolar oil will not dissolve into the polar. The oil forms the top layer because it is less dense than the water.
    ::水和石油在混合时形成不同的层层,因为非极油不会溶解到极中。 石油形成顶层,因为它比水密度低。

    For , the major factor that contributes to the material dissolving in water is the ability to form with the water solvent .  Small compounds such as methanol, ethanol, acetic , and acetone have polar groups that can interact with the polar H of water.  However, as the nonpolar portion of the molecule gets larger, with water drops off.  The nonpolar portion of the molecule increasingly repels to water and eventually overrides the interaction of the polar component with water.
    ::导致水中物质溶解的主要因素是能否与水溶剂形成,小型化合物,如甲醇、乙醇、乙醇、乙酸、丙酮和丙酮,有极地组,可以与水的极H相互作用,然而,随着分子的非极化部分增加,水滴就会下降,分子的非极化部分越来越多地向水中扩散,最终超越极化部分与水的相互作用。

    What is the difference between miscible and immiscible liquids?
    ::混相液体和不混相液体的区别是什么？

    To describe how well liquids mix together chemists use the term miscible. If two liquids are miscible, when they are mixed together, the two liquids will combine to form a homogeneous solution. In this video, Robin Higgins, describes the difference between miscible and immiscible liquids. 
    ::描述液体混合的化学家们如何使用不当的术语。 如果两种液体是不强迫的,当它们混合在一起时,两种液体会合在一起形成一种同质的溶液。在这个视频中,罗宾·希金斯描述了不强迫和不强迫的液体之间的区别。

     

    Summary
    ::摘要

    • Nonpolar molecules are usually insoluble in water.
      ::非极分子通常无法溶解于水中。
    • A nonionized molecule must be relatively polar to interact with water molecules.
      ::一个非电离分子必须相对极化,才能与水分子发生相互作用。

    Review
    ::回顾

    1. What are the main attractive forces that operate between nonpolar molecules?
      ::在非极分子之间起作用的主要吸引力量是什么?
    2. Will water dissolve polar or nonpolar molecules?
      ::水会溶解极分子或非极分子吗?
    3. List at least three organic molecules that will dissolve well in water.
      ::列出至少三个会在水中溶解的有机分子。