Main->Readings->5th Grade Readings->Chemistry->Part 1: Studying Matter
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Scientists may seem quiet, but they are explorers and adventurers. Sometimes, they explore the farthest parts of the universe. Other times, they discover strange new life forms here on Earth. And sometimes they look at what is right in front of us.
Mostly, what is in front of us is matter. Matter is the stuff that makes everything in the universe. You are made of matter, the air around you is made of matter, and the Earth beneath your feet is made of matter. A chemist (KEM-ist) is someone who studies matter, how it is put together, what it is made of, and how it acts.
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People have been curious about matter since the beginning of civilization. For instance, the ancient Greeks used to wonder about it. Some thought maybe everything you could see and feel was really made from water. Others thought it was made of fire. Some other Greeks, including Aristotle, figured it must be made out of earth and air as well as fire and water. A Greek called Leucippus (loo-SIP-uss) and his student Democritus (dem-OCK-ri-tuss) thought maybe instead that matter was made out of tiny particles called atoms. Leucippus and Democritus were closest to the truth. However, the Greeks were philosophers, not scientists. That is, they came up with ideas, but did not do anything to check their ideas. |
It was not until the late 1700s that the true science of chemistry was born. A science is a way of learning knowledge which uses careful methods to test ideas and observations. The science which studies matter is called chemistry (KEM-iss-tree).
In medieval times, there were people called alchemists. They mixed science up with other things. They studied matter, but they spent their time trying to turn cheap metals into gold or trying to invent the elixir of life which would make people immortal. Because they were not willing to change their ideas, they did not discover anything new.
In the 1600s and 1700s, however, things began to change. The scientific method was born, a way of really learning new things.
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Using this method, scientists discovered some astounding things about matter.
The first thing we do when we talk about studying matter is to agree on what matter is. You could say matter is everything in the universe, but there are plenty of things that are not matter. Light is not matter, and neither is electricity. Magnetism is not matter either. We say matter is anything that takes up space and has mass.
When something takes up space, it has volume. Volume is the size of something, in other words the amount of space something takes up. The volume of a liquid or a powder can be measured with a container such as a graduate or a measuring cup. The volume of a solid can be measured with a ruler if it has a regular shape (like a box or a pyramid) or by displacement of water (that is, by dropping it into a container and seeing how much the water rises).
Measuring volume with a graduate
Measuring volume with a ruler
Measuring volume by displacement of water
Mass describes the amount of matter in something. You can measure the mass of a piece of matter by comparing it to another piece of matter on a balance or scale.
Measuring mass with a balance
| Although mass is related to weight, it isn't exactly the same thing. Weight describes how hard gravity is pulling on you, and it can change depending on where you are. On the Earth, for instance, you weigh more than you would on the Moon because gravity is stronger on the Earth. Even if you traveled to the Moon, your mass would not change, however, because you would still have the same amount of matter in you. |
The second thing we have to do is agree on ways to describe matter. A property of matter is a way of describing it. We have already talked about volume and mass. The volume of something is a property of matter, and so is the mass of something. Other properties of matter include things like color, shape, hardness, temperature, odor, and texture.
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Some properties of matter:
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Properties of a rubber ball
Chemists have made lists of ways to describe and measure properties. They prefer properties that can be measured, because it is easier to describe and compare different kinds of matter using numbers. You can test the hardness of a substance, or find its boiling temperature, and give it a number. This makes it easy to compare different kinds of matter.
The third thing scientists must do to study matter is to classify it into groups. You will learn about the classification of matter in the next section.
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Go on to Part Two: Classifying Matter
This page last modified August 15, 2002
Questions? Send me a note at dturner@haverford.org