91 Mixing Matter-High

Mixing Matter Written by Lance Campbell

兰斯·坎贝尔(Lance Campbell)著

Introduction Look at the things around you. You probably see things with many different properties. You may see books, a chair, and some water. All these things are types of matter. A balloon and the air you blow into it are types of matter. Everything in the universe that takes up space and has weight is made of matter. But what exactly is matter? And what makes the many kinds of matter different? How can matter be mixed to create new things? This book explores these and other questions to help you better understand what matter is and how it can change.

看看你周围的事物。 你可能会看到很多不同性质的东西。 你可以看到书，一把椅子和一些水。 所有这些都是物质的类型。 气球和你吹进去的空气都是物质。 宇宙中所有占据空间并有重量的东西都是由物质构成的。 但究竟什么是物质呢? 是什么让这些物质变得不同呢? 物质是如何混合起来创造新事物的呢? 这本书探讨了这些和其他问题，以帮助你更好地理解物质是什么以及它如何变化。

Elements All matter is made of simple substances called elements. An element is a substance that cannot be broken down into a simpler substance. There are about 120 known elements on Earth. Substances can be made of a single element. Pure iron, gold, and silver are each made of a single element. They cannot be made into simpler substances. But most substances we know of are a combination of two or more elements. Sugar is a substance made of three elements, while salt is a substance made of two elements. This means that both sugar and salt can be broken down into the simpler elements they are made of.

所有物质都是由称为元素的简单物质构成的。 元素是一种不能被分解成更简单的物质的物质。 地球上已知的元素大约有120种。 物质可以由单一元素构成。 纯铁、金、银都是由一种元素构成的。 它们不能被制成更简单的物质。 但我们所知道的大多数物质都是两种或两种以上元素的结合体。 糖是由三种元素组成的物质，而盐是由两种元素组成的物质。 这意味着糖和盐都可以被分解成组成它们的更简单的元素。

Each element can be identified using a symbol. Many symbols are the first one or two letters of the element's name. For example, helium is "He," carbon is "C," and oxygen is "O." The images above show some common elements and their symbols. Word Wise Some symbols for elements come from Latin. Fe is the symbol for the element iron. Fe is short for ferrum, the Latin word for iron. Au is the symbol for the element gold. Au is short for aurum, the Latin word for gold.

每个元素都可以用一个符号来标识。 许多符号是元素名称的前一个或两个字母。 例如，氦是“He”，碳是“C”，氧是“o”。 上图显示了一些常见的元素及其符号。 一些元素的符号来自拉丁语。 Fe是铁元素的符号。 Fe是拉丁文中铁的缩写ferrum。 Au是金元素的符号。 Au是金的拉丁文aurum的缩写。

Atoms Imagine that you had the power to look deep inside any substance or material. If you had this power, you would see that all matter, and therefore all elements, are made of tiny, invisible particles called atoms. Different elements are made of different atoms. Atoms are the smallest part of an element. If you could look into a gold coin, you would see that it is made of millions of gold atoms. If you could see inside a balloon filled with helium, you would see that the helium gas is made of millions of helium atoms.

想象一下，你有能力深入观察任何物质或材料的内部。 如果你有这种能力，你就会看到所有的物质，因此所有的元素，都是由微小的、看不见的粒子——原子构成的。 不同的元素由不同的原子构成。 原子是元素中最小的部分。 如果你能观察一枚金币，你会发现它是由数百万个金原子组成的。 如果你能看到一个氦气球的内部，你就会发现氦气是由数百万个氦原子组成的。

Let's further imagine that you had super powers that let you see inside an atom. You would see that atoms are made of even smaller particles. The structure of an atom is in some ways like the structure of the Solar System. In the solar system, planets orbit, or go around, the Sun. In an atom, tiny particles called electrons orbit the nucleus, or center of the atom. The nucleus of an atom is like the Sun around which planets revolve. The nucleus is made of two kinds of particles— protons and neutrons. All atoms of the same element have the same number of protons and electrons. As tiny as atoms are, they have mass. Most of the mass of an atom is in the nucleus. So the more protons and neutrons an atom has, the more mass it has. A helium atom has 2 protons and 2 neutrons in its nucleus. This makes helium the second- lightest element. (The lightest is hydrogen.) Lead, on the other hand, has 82 protons and 125 neutrons, so it is much heavier than helium.

让我们进一步想象一下，你有超能力，可以看到原子的内部。 你会发现原子是由更小的粒子组成的。 原子的结构在某些方面类似于太阳系的结构。 在太阳系中，行星围绕太阳运行。 在原子中，被称为电子的微小粒子围绕原子核或原子中心运行。 原子核就像太阳一样，行星围绕着太阳旋转。 原子核是由两种粒子构成的——质子和中子。 同一元素的所有原子都有相同数量的质子和电子。 原子虽小，却有质量。 原子的大部分质量在原子核中。 所以一个原子的质子和中子越多，它的质量就越大。 一个氦原子的原子核中有2个质子和2个中子。 这使得氦成为第二轻的元素。 (最轻的是氢。)另一方面，铅有82个质子和125个中子，所以它比氦重得多。