章节大纲

  • Lesson Objectives
    ::经验教训目标

    • Describe matter in the solid state.
      ::描述物质以坚固的状态。
    • State properties of liquid matter.
      ::液体物质状态。
    • Identify properties of gases.
      ::标明气体的特性。
    • Explain the relationship between energy and states of matter.
      ::解释能源与物质状态之间的关系。

    Lesson Vocabulary
    ::词汇表课程

    • energy
      ::能源能源
    • gas
      ::气体气体气体
    • kinetic energy
      ::动动能能量
    • kinetic theory of matter
      ::物质动态理论
    • liquid
      ::液态液体
    • solid
      ::固体
    • states of matter
      ::事态状态

    Introduction
    ::导言

    Matter can be found in different forms. These different forms are called  States of Matter . Look at  Figure . It represents water in three states. Water can exist as a solid, like an iceberg. It can also exist as a liquid, such as the ocean. Finally, water can exist as a gas. We know this form of water as water vapor.  Water vapor is completely invisible. In the figure below, you cannot see the water vapor, but it is there. The clouds you see are not water vapor. Clouds can be made of tiny droplets of liquid water. They can also contain ice crystals.
    ::物质可以以不同的形式找到。 这些不同的形态被称为物质状态。 看看图。 它代表了三个状态中的水。 水可以作为固体存在, 像冰山一样。 它也可以作为液体存在, 比如海洋。 最后, 水也可以作为液体存在, 比如海洋。 最后, 水可以作为气体存在。 我们知道这种水的形式是水蒸气。 水蒸气是完全看不见的。 在下图中, 你看不到水蒸气, 但是它在那里。 你看到的云不是水蒸气。 云可以由微小的液水滴组成, 它们也可以包含冰晶 。

    Water in all three states is still water. All three forms have the same chemical makeup. They also share the same chemical properties. That's because the state of matter is a physical property. The change in the state of water is a physical change. This means it is reversible. Water molecules can freeze into a solid and melt back to a liquid. Water molecules can change from a liquid to a gas and back again. It can pass through all of its states and it is still water. 
    ::所有三个州的水都是水。 所有三个形式的水都是相同的化学成分。 它们都有相同的化学特性。 这是因为物质状态是物理属性。 水状态的变化是物理属性的改变。 这意味着水状态的变化是可逆的。 水分子可以冷冻成一个固体, 融化成液态。 水分子可以从液态变成气体, 然后再从气体。 它可以穿过所有状态, 它仍然是水。

    lesson content
     
    This photo represents solid, liquid, and gaseous water. Where is the gaseous water in the picture?

    How do solids, liquids, and gases differ? Their properties are compared in  Figure   and described below. You can also watch videos about the three states.
    ::固体、液体和气体如何不同?它们的特性在下图中比较并描述。您也可以观看关于这三个状态的视频。

     

    lesson content
     
    These three states of matter are common on Earth. What are some substances that usually exist in each of these states?

    Solids
    ::固体

    Ice is an example of a solid. A solid occurs when matter has a fixed volume and a fixed shape. The particles of solids are arranged in a regular repeating pattern. The structure of a solid is rigid. This simply means it does not change shape. Think of an ice cube. Its shape will not change unless it is melted. 
    ::冰是固体的一个例子。 当物质有一个固定的体积和一个固定的形状时, 就会有固体。 固体的颗粒会以常规的重复模式排列。 固态的结构是硬的。 这仅仅意味着它不会改变形状。 想象一个冰块。 它的形状不会改变, 除非它被熔化 。

    lesson content
     
    The volume and shape of a solid can be changed, but only with outside help. How could you change the volume and shape of each of the solids in the figure without changing the solid in any other way?

    Liquids
    ::流动液体

    Ocean water is an example of a liquid. A liquid is matter that has a fixed volume but not a fixed shape. No matter what the shape of the container, the amount of water will stay the same. Liquids take the shape of the container they are in. We must assume the volume of a liquid is less than the volume of its container. Otherwise, it would overflow. 
    ::海洋水是液体的一个例子。液体是具有固定体积但非固定形状的物质。不管容器的形状如何,水量将保持不变。液体是容器的形状。液体是容器的形状。我们必须假设液体的体积小于容器的体积。否则,液体会溢出。

    lesson content
     
    Each bottle contains the same volume of oil. How would you describe the shape of the oil in each bottle?

    Gases
    ::气体气体

    Water vapor is an example of a gas. A gas is matter that does not have a fixed volume or a fixed shape. Instead, a gas takes both the volume and the shape of its container. It spreads out to take up all available space. You can see an example of a gas in the  Figure  . In this case, the gas is air. 
    ::水蒸气是气体的一个例子。 气体是没有固定体积或固定形状的物质。 相反, 气体的体积和容器的体积都与容器的体积相同。 它会扩散到所有可用的空间。 您可以在图中看到气体的例子。 在这种情况下, 气体就是空气。

    lesson content
     
    When you add air to a bicycle tire, you add it only through one tiny opening. But the air immediately spreads out to fill the whole tire.

    Energy and Matter
    ::能源和能源事项

    Why are there different states of matter? It is because they have different amounts of energy. Energy affects the motion of particles. Atoms and molecules are the particles that make up matter. The amount of energy affects their behavior, but why? 
    ::为什么物质状态不同?这是因为它们有不同的能量量。能源影响粒子运动。原子和分子是构成物质的粒子。能量量影响它们的行为,但为什么呢?

    Energy
    ::能源能源能源

    Simply put,  energy  is the ability to a cause change. Energy can cause many types of change. Think about when you have a lot of energy. You are able to do a lot of things. When you don't have a lot of energy, you may sit around and do very little. A similar thing happens to particles of matter as energy is added. The more energy there is, the faster the particles of matter move.
    ::简言之,能源是改变原因的能力。能源可以带来许多类型的变化。想想当你拥有大量能量的时候,你可以做很多事情。当你没有太多能量的时候,你可以坐着做很少的事情。在物质粒子上也会发生类似的事情,比如增加能量。能量越多,物质粒子移动的速度就越快。

    Energy is also the reason you are able to move around. In fact, matter is always in motion. It can even change from one form to another. For example, electrical energy can be converted into heat energy. You see this every time you use the toaster. Energy causes a change in matter when you lift your arm. Energy can be used to move matter. You use energy to take a step to move forward. Thanks to energy, your body moves. The energy of moving matter is called  kinetic energy .
    ::能源也是你能够移动的原因。 事实上, 物质总是在运动。 它甚至可以从一种形式变化到另一种形式。 例如, 电力能可以转换成热能。 每次使用烤面包机都能看到这一点。 当你举起手臂时, 能源可以改变物质。 能源可以用来移动物质。 能源可以用来移动物质。 你用能源前进。 多亏能源, 你的身体可以移动。 移动物质的能量被称为动能。

    Kinetic Theory of Matter
    ::物质动态理论

    The particles that make up matter are also constantly moving. They have kinetic energy. Scientists use  kinetic theory of matter  to explain how matter moves. You can learn more about it in the video below.
    ::构成物质的粒子也在不断移动。 它们有动能。 科学家使用动能理论来解释物质如何移动。 您可以在下面的视频中了解更多关于它的知识 。

     

    The more energy that is present, the faster matter is able to move. Particles that are moving really fast get further apart. The faster they move the more they spread apart. How do you think this happens? 
    ::能量越多, 物质就能移动得越快。 移动速度越快的粒子越快, 移动速度越快。 移动速度越快, 扩散越快。 您认为这种情况会如何发生 ?

    Lesson Summary
    ::经验教训摘要

    • A solid is matter that has a fixed volume and a fixed shape.
      ::固体是具有固定体积和固定形状的物质。
    • A liquid is matter that has a fixed volume but not a fixed shape.
      ::液体是具有固定体积但非固定形状的物质。
    • A gas is matter that has neither a fixed volume nor a fixed shape.
      ::气体是既无固定体积,又无固定形状的物质。
    • The state of matter depends on the amount of kinetic energy. 
      ::物质状态取决于动能的量。

    Lesson Review Questions
    ::经验回顾问题

    Recall
    ::回顾

    1. What are states of matter?
      ::什么是状况?
    1. What are the properties of solids?
      ::固体的特性是什么?
    1. State the properties of liquids.
      ::说明液体的特性。
    1. Describe properties of gases.
      ::描述气体的特性。

    Think Critically
    ::仔细仔细思考

    1. Explain the relationship between energy and states of matter.
      ::解释能源与物质状态之间的关系。

    Points to Consider
    ::需要考虑的要点

    You read in this lesson that gases expand to fill their container.
    ::你在这个课中读到 气体膨胀以填充容器

    • What if gas were forced into a smaller container? Would it shrink to fit?
      ::如果煤气被迫进入一个较小的容器,那么它会缩缩到更小的容器里吗?
    • What other properties of the gas might change if its particles were crowded closer together?
      ::如果气体的粒子聚集得更近一点,气体的其他特性会有什么变化?