Oxygen Lesson for Kids: Definition & Facts

Instructor: Mary Beth Burns

Mary Beth has taught 1st, 4th and 5th grade and has a specialist degree in Educational Leadership. She is currently an assistant principal.

Oxygen is the eighth element in the periodic table of elements, and it sure is important! Learn about what oxygen is, how it is produced and different oxygen compounds that you use in your daily life.

What Is oxygen?

What is something that's invisible, has no taste or smell, and doesn't make a sound--but you couldn't live without it? Oxygen, of course! Oxygen is the eighth element on the periodic table of elements, where it's represented by the letter O. An element is the simplest form of matter there is--it can't be broken down into any simpler parts.

Chemists call the air that we breathe O2 because there are two atoms in the oxygen molecule. The ozone, the layer of the atmosphere that protects you from the sun's ultraviolet rays, is called 03. Why, you ask? Because there are three atoms in the oxygen molecule.

Can you find oxygen on the periodic table?

Oxygen is all around us. It's in the air, water and even the human body. Did you know that 65% of your body weight is oxygen? Most of the oxygen in your body can be found in your bloodstream and lungs.

Without oxygen, you would not be able to breathe. In fact, there wouldn't be any living things on Earth if it weren't for oxygen. Have you ever wondered why humans do not live on other planets in our solar system? Earth is the only planet that has the perfect amount of oxygen in the atmosphere at 21%--not too little, not too much. Yes, there is such a thing as too much oxygen. If you breathe in too much oxygen, it can be toxic and you would get very sick.

How Is Oxygen Produced?

Oxygen can be produced naturally or it can be man-made. One of the most common ways that oxygen is produced in nature is by photosynthesis. Photosynthesis is when plants use energy from the sun and convert, or change, it into chemical energy that it uses for food.

Photosynthesis produces oxygen.

During the first step of photosynthesis, the plant converts water into oxygen using light energy from the sun. This is one reason why many people are passionate about preventing the cutting down of trees and forests. Without trees, the Earth's oxygen levels would be much lower.

Hydrogen and oxygen are separated in electrolysis.

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