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  • 道尔顿原子理论

    An atom with protons, neutrons, and electrons in orbit.

    You probably know what this sketch represents. It’s a model of an , one of the miniscule particles that make up all matter. The idea that matter consists of extremely tiny particles called atoms was first introduced about 2500 years ago by a Greek philosopher named Democritus. However, other philosophers considered Democritus’ idea ridiculous, and it was more or less forgotten for more than 2000 years.
    ::你也许知道这个草图代表着什么。它是一个模型,它是一个组成所有物质的微小粒子。 物质是由叫做原子的极小粒子组成的理念是大约2500年前由希腊哲学家Democrictitus首次提出的。 然而,其他哲学家认为民主思想是荒谬的,而且它被遗忘了2000多年。

    Reintroducing the Atom
    ::重新引入原子

    Around 1800, the English chemist John Dalton brought back Democritus’ ancient idea of the atom. You can see a picture of Dalton . Dalton grew up in a working-class family. As an adult, he made a living by teaching and just did research in his spare time. Nonetheless, from his research he developed one of the most important theories in all of science . Based on his research results, he was able to demonstrate that atoms actually do exist, something that Democritus had only guessed.
    ::大约1800年,英国化学家约翰·道尔顿(John Dalton)带回了民主党对原子的古老想法。 你可以看到道尔顿(Dalton ) 。 道尔顿(Dalton)是在工人阶级家庭中长大的。 作为一个成年人,他靠教书谋生,在业余时间做研究。 尽管如此,从他的研究中,他开发出了所有科学中最重要的理论之一。 根据他的研究成果,他能够证明原子确实存在,而民主主义只是猜测了这一点。

    Portrait of John Dalton, an English chemist known for developing atomic theory.

    Dalton’s Experiments
    ::道尔顿实验

    Dalton did many that provided evidence for the existence of atoms. For example:
    ::Dalton做了很多证明原子存在的证据。例如:

    • He investigated pressure and other properties of , from which he inferred that gases must consist of tiny, individual particles that are in constant, random motion.
      ::他调查了...的压力和其他特性,从中他推断,气体必须由不断随机运动的微小、个别微粒组成。
    • He researched the properties of compounds, which are substances that consist of more than one . He showed that a given is always comprised of the same elements in the same whole-number ratio and that different compounds consist of different elements or ratios. This can happen, Dalton reasoned, only if elements are made of separate, discrete particles that cannot be subdivided.
      ::他研究了化合物的特性,化合物是由多个物质构成的。他表明,一个特定物质总是由相同元素组成的,其整数比率相同,不同的化合物由不同的元素或比率组成。 道尔顿说,只有当元素由无法细分的分离粒子组成时,才会发生这种情况。

    Atomic Theory
    ::原子理论

    From his research, Dalton developed a theory about atoms. consists of three basic ideas:
    ::Dalton从他的研究中 形成了关于原子的理论 由三个基本想法组成:

    • All substances are made of atoms. Atoms are the smallest particles of matter. They cannot be divided into smaller particles, created, or destroyed.
      ::所有物质都是由原子制成的,原子是物质中最小的粒子,不能分为较小的粒子、创造或销毁。
    • All atoms of the same element are alike and have the same mass. Atoms of different elements are different and have different masses.
      ::同一元素的所有原子都相似,质量相同,不同元素的原子不同,质量也不同。
    • Atoms join together to form compounds, and a given compound always consists of the same kinds of atoms in the same proportions.
      ::原子合在一起形成化合物,而特定化合物总是由同一比例的相同原子组成。

    Dalton’s atomic theory was accepted by many scientists almost immediately. Most of it is still accepted today. However, scientists now know that atoms are not the smallest particles of matter. Atoms consist of several types of smaller particles, including , , and electrons. 
    ::道尔顿的原子理论几乎立即被许多科学家所接受。 大部分理论今天仍然被接受。 但是,科学家现在知道原子不是最小的物质粒子。 原子由几种小粒子组成,包括 、 和电子。

    The Billiard Ball Model
    ::Billiard 球球模型

    Because Dalton thought atoms were the smallest particles of matter, he envisioned them as , hard spheres, like billiard (pool) balls, so he used wooden balls to model them. Three of his model atoms are pictured in the Figure . Do you see the holes in the balls? Dalton added these so the model atoms could be joined together with hooks and used to model compounds.
    ::因为道尔顿认为原子是物质中最小的粒子, 他把原子想象成硬球,如球球, 所以他用木球来模拟它们。 图中描绘了三个模型原子。 你看到球中的洞吗? 道尔顿添加了这些, 这样模型原子就可以与钩子结合起来, 并用来模拟化合物。

    Three wooden balls representing Dalton's model of atoms, featuring holes for hooks to connect them.

    Q: When scientists discovered smaller particles inside the atom, they realized that Dalton’s atomic models were too simple. How do modern atomic models differ from Dalton’s models?
    ::问题:当科学家在原子中发现小粒子时,他们意识到道尔顿的原子模型太简单。 现代原子模型与道尔顿模型有什么不同?

    A: Modern atomic models, like the one pictured at the top of this article, usually represent subatomic particles, including electrons, protons, and neutrons.
    ::A:现代原子模型,如同本文章顶部所描绘的模型,通常代表亚原子粒子,包括电子、质子和中子。

    Summary
    ::摘要

    • Around 1800, the English chemist John Dalton reintroduced the idea of the atom, which was first introduced by the ancient Greek philosopher named Democritus.
      ::大约1800年左右,英国化学家约翰·道尔顿重新提出了原子的理念,这是古希腊哲学家、名为“民主”的古希腊哲学家首次提出的。
    • Dalton did many experiments with gases and compounds that provided evidence for the existence of atoms.
      ::道尔顿用气体和化合物做了许多实验 证明了原子的存在
    • Dalton developed an atomic theory that is still mostly accepted today. It is one of the most important theories in all of science.
      ::道尔顿发明了一种原子理论,今天大部分人仍然接受它。它是所有科学中最重要的理论之一。
    • Dalton thought individual atoms were solid, hard spheres, so he modeled them with wooden balls.
      ::道尔顿认为个体原子是坚固的 坚硬的球体 所以他用木球模拟了它们

    Review
    ::回顾

    1. Who was John Dalton?
      ::约翰·道尔顿是谁?
    2. What evidence did Dalton use to argue for the existence of atoms?
      ::道尔顿用什么证据来证明原子的存在?
    3. State Dalton’s atomic theory.
      ::州道尔顿的原子理论。
    4. Explain how Dalton modeled atoms and compounds.
      ::解释道尔顿是如何模拟原子和化合物的

    Resources
    ::资源