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Oxygen

physical science Maturity 11-13 Vital Level 3

The air has a special part.

Oxygen molecule.png
Oxygen molecule.png
It helps us live. Plants make it for us.
Simple photosynthesis overview.svg
Simple photosynthesis overview.svg
We need it to breathe. It is all around you. Do you feel the air?

35 words

The air has a special part.

Oxygen molecule.png
Oxygen molecule.png
It helps us live. Plants make it for us.
Simple photosynthesis overview.svg
Simple photosynthesis overview.svg
They catch sunlight to make food. This makes the air for us to breathe. Most living things need it. It helps us get energy from food. This gas is also in water. It is even in your bones. It is all around you. Do you feel the air?
Stilles Mineralwasser.jpg
Stilles Mineralwasser.jpg

70 words

Oxygen is a very important part of our world.

Oxygen molecule.png
Oxygen molecule.png
It is a gas that is all around us. It makes up about 20.95% of the air we breathe.
Simple photosynthesis overview.svg
Simple photosynthesis overview.svg
Plants help make this oxygen. They use sunlight to make food. During this way, they let out oxygen as a byproduct.

Most living things need oxygen to stay alive. It helps them with cellular respiration. This is a way to get power from food. It also lets out carbon dioxide as waste. Oxygen is also found in many other things. It is a part of water. It is even in our bones and teeth.

Scientists worked for a long time to understand it. Joseph Priestley was one of the first to publish his work. He saw that candles burned brighter in it.

PriestleyFuseli.jpg
PriestleyFuseli.jpg
Later, Antoine Lavoisier showed it was a real element.
Lavoisier, Antoine Laurent de (1743-1794) CIPB1171.jpg
Lavoisier, Antoine Laurent de (1743-1794) CIPB1171.jpg
He also explained how it helps things burn. Today, we use oxygen for many jobs. It helps make steel and even helps rockets fly.
Goddard and Rocket.jpg
Goddard and Rocket.jpg

178 words

Oxygen is a very important chemical element. It is a member of the chalcogen group in the periodic table.

Oxygen molecule.png
Oxygen molecule.png
This element is highly reactive. This means it loves to bond with other things. It forms oxides with most elements. Oxygen is the most abundant element in the Earth's crust. It makes up almost half of the crust. You can find it in water and carbon dioxide. It is also in iron oxides and silicates.
Rust screw.jpg
Rust screw.jpg
In space, it is the third-most abundant element. Only hydrogen and helium are more common.

Most oxygen in our air is a gas called dioxygen.

Oxygen molecule orbitals diagram-en.svg
Oxygen molecule orbitals diagram-en.svg
Two oxygen atoms bind together to form this gas. It has no color and no smell. This gas makes up about 20.95% of our atmosphere. There is also a rarer form called ozone.
Oxygen molecule.png
Oxygen molecule.png
Ozone forms a protective layer in the stratosphere. This layer shields life from harmful ultraviolet radiation. However, ozone at the surface is an air pollutant. It is a corrosive byproduct of smog. Living things use oxygen for cellular respiration.
Simple photosynthesis overview.svg
Simple photosynthesis overview.svg
This is a way to get stored energy from food. During this, oxygen reacts with organic molecules. This process releases carbon dioxide as a waste product.

Many people helped us understand oxygen over many centuries.

PriestleyFuseli.jpg
PriestleyFuseli.jpg
Michael Sendivogius described a substance in the air before 1604. He called it the "food of life." Later, Carl Wilhelm Scheele produced oxygen in 1771. Joseph Priestley also discovered it in 1774. Priestley was the first to publish his findings. He called the gas "dephlogisticated air." He did not know it was a real element.
Lavoisier, Antoine Laurent de (1743-1794) CIPB1171.jpg
Lavoisier, Antoine Laurent de (1743-1794) CIPB1171.jpg
Antoine Lavoisier was the first to recognize it as an element. He did this in 1777. He also explained how it works in combustion.

Scientists used to believe in the phlogiston theory. This theory said things burned by losing a substance called phlogiston.

Lavoisier, Antoine Laurent de (1743-1794) CIPB1171.jpg
Lavoisier, Antoine Laurent de (1743-1794) CIPB1171.jpg
Lavoisier proved this was wrong with careful experiments. He heated tin in a closed container. He saw the tin increased in weight. This happened because it took oxygen from the air.
Stilles Mineralwasser.jpg
Stilles Mineralwasser.jpg
Lavoisier named the element oxygen in 1777. He used Greek roots meaning "acid producer." He thought oxygen was in all acids. He was actually wrong about that part. But the name stuck and we still use it today.

We use oxygen for many important jobs in our world.

Goddard and Rocket.jpg
Goddard and Rocket.jpg
Factories use it to make steel, plastics, and textiles. It is used in welding and cutting metals. Oxygen is also used as rocket propellant.
Goddard and Rocket.jpg
Goddard and Rocket.jpg
Doctors use oxygen therapy to help people breathe. It is also used in life-support systems. These systems are needed for aircraft and submarines. Divers and astronauts also need it to survive. Oxygen is truly a part of almost everything we do.

482 words

{ "text": "Oxygen is a chemical element with the symbol O and the atomic number 8. It is a member of the chalcogen group in the periodic table. As a nonmetal, oxygen is highly reactive with most other elements. It acts as a potent oxidizing agent, which means it readily forms oxides through chemical reactions.

Oxygen molecule.png
Oxygen molecule.png
Oxygen is incredibly abundant in our world. It makes up almost half of the Earth's crust. This occurs through various oxides like water, carbon dioxide, iron oxides, and silicates. In the wider universe, it is the third-most abundant element, following only hydrogen and helium.\n\nIn our atmosphere, oxygen primarily exists as a diatomic gas called dioxygen. At standard temperature and pressure, two oxygen atoms bind covalently to form this gas.
Oxygen molecule orbitals diagram-en.svg
Oxygen molecule orbitals diagram-en.svg
Dioxygen is colorless and odorless. It currently makes up a 20.95% molar fraction of the Earth's atmosphere. Another form, known as an allotrope, is called ozone (O3).
Oxygen molecule.png
Oxygen molecule.png
Ozone is much rarer and forms a

166 words
🖼️ Images & Media (23)
File:PriestleyFuseli.jpg
PriestleyFuseli.jpg
File:Lavoisier, Antoine Laurent de (1743-1794) CIPB1171.jpg
Lavoisier, Antoine Laurent de (1743-1794)...
File:Goddard and Rocket.jpg
Goddard and Rocket.jpg
File:Oxygen molecule orbitals diagram-en.svg
Oxygen molecule orbitals diagram-en.svg
File:Liquid oxygen in a magnet 2.jpg
Liquid oxygen in a magnet 2.jpg
File:Oxygen molecule.png
Oxygen molecule.png
File:Liquid oxygen in a beaker 4.jpg
Liquid oxygen in a beaker 4.jpg
File:Evolved star fusion shells.svg
Evolved star fusion shells.svg
File:WOA09 sea-surf O2 AYool.png
WOA09 sea-surf O2 AYool.png
File:Phanerozoic Climate Change.png
Phanerozoic Climate Change.png
File:Simple photosynthesis overview.svg
Simple photosynthesis overview.svg
File:Oxygenation-atm.svg
Oxygenation-atm.svg

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