The Earth is one large mixture of gases, liquids and solids.
Matter is everything around you. Atoms and molecules are all composed of matter. Matter is anything that has mass and takes up space. If you are new to the idea of mass, it is the amount of stuff in an object. We talk about the difference between mass and weight in another section. Matter is sometimes related to light and electromagnetic radiation.
Even though matter can be found all over the Universe, you will only find it in a few forms on Earth. We consider five states of matter. Each of those states is sometimes called a phase. There are many other states of matter that exist in extreme environments. Scientists will probably discover more states as we continue to explore the Universe.
Five States of Matter
Five States of Matter: Condensate, Solid, Liquid, Gas, Plasma
You should know about solids, liquids, gases, plasmas, and one state called the Bose-Einstein condensate (BEC). Scientists have always known about solids, liquids, and gases. Plasma was a new idea when it was identified by William Crookes in 1879. The scientists who worked with the Bose-Einstein condensate received a Nobel Prize for their work in 1995.
What makes a state of matter? It's about the physical state of the molecules and atoms. Think about solids. They are often hard and brittle. Liquids are fluidy, can move around a little, and fill up containers. Gases are always around you, but the molecules of a gas are much farther apart than the molecules in a liquid. If a gas has an odor, youll be able to smell it before you can see it. The BEC is all about atoms that are even closer and less energetic than atoms in a solid.
Changing States of Matter
Physical change of water into ice versus chemical change of hydrogen peroxide into water.
Molecules can move from one physical state to another and not change their basic structure. Oxygen (O2) as a gas has the same chemical properties as liquid oxygen. The liquid state is colder and denser, but the molecules (the basic parts) are still the same. Water (H2O) is another example. A water molecule is made up of two hydrogen (H) atoms and one oxygen (O) atom. It has the same molecular structure whether it is a gas, liquid, or solid. Although its physical state may change, its chemical state remains the same.
So you're asking, "What is a chemical change?" Let's start with a glass of pure water. If the formula of water were to change, that would be a chemical change. If you could add a second oxygen atom to a water molecule, you would have hydrogen peroxide (H2O2). The molecules would not be water anymore. The reality of creating hydrogen peroxide is more difficult.
Chemical changes occur when the bonds between atoms in a molecule are created or destroyed. Changes in the physical state are related to changes in the environment such as temperature, pressure, and other physical forces. Generally, the basic chemical structure does not change when there is a physical change. Of course, in extreme environments such as the Sun, no molecule is safe from destruction.
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Atoms Around Us
You are made of different types of atoms.
Atoms are building blocks. If you want to create a language, you'll need an alphabet. If you want to build molecules, you will need atoms of different elements. Elements are the alphabet in the language of molecules. Each element is a little bit different from the rest.
Atoms are the general term used to describe pieces of matter. You have billions of billions of atoms in your body. However, you may only find about 40 elements. You will find billions of hydrogen (H) atoms, billions of oxygen (O) atoms, and a bunch of others. All of the atoms are made of the same basic pieces, but they are organized in different ways to make unique elements.
Common Elements
Common elements can build very different molecules.
Let's work with that idea for a bit. If you read a book, you will find words on each page. Letters make up those words. In English, we only have twenty-six letters, but we can make thousands of words. In chemistry, you are working with almost 120 elements. When you combine them, you can make millions of different molecules.
Molecules are groups of atoms bonded together in the same way that words are groups of letters. An "A" will always be an "A" no matter what word it is in. A sodium (Na) atom will always be a sodium atom no matter what compound it is in. While the atoms have different masses and organization for each element, they are all built with the same parts. Electrons, protons, and neutrons make the Universe the way it is.
From Simple to Complex
Small parts combine to form larger structures.
Super-tiny subatomic particles are used to create the parts of atoms. Protons, neutrons, and electrons can then organize to form atoms. Atoms are then used to create the molecules around us. There are almost 120 elements that can be found in the molecules we know. Smaller molecules can work together and build macromolecules. It just goes on. Everything you see or imagine is built from something else.
