Oxygen is an element found as a gas at room temperature. It makes up 21% of the composition of the atmosphere. The discovery of this element gave us a better understanding of chemical reactions, specifically combustion and respiration. Respiration is a chemical reaction which is essential for life.
Oxygen is the 8th element on the periodic table. It makes up 21% of the Earth’s atmosphere and is essential to life. It is normally found as a diatomic molecule, which is a colorless, odorless gas, but can also be found as O3, known as ozone. Half of the Earth’s atmosphere is made of compounds which contain oxygen.
The ozone layer is a layer around the Earth that is made up of high concentrations of ozone. This layer absorbs large amounts of the Sun’s UV rays before they reach the surface. This UV light would be very harmful to life on Earth we weren’t shielded by the atmosphere.
Respiration is a chemical reaction all living things use to release energy from nutrients. Inside cells, oxygen reacts with glucose to produce carbon dioxide and water (C6H12O6 + 6O2 → 6CO2 + 6H2O) This is an essential reaction for life on Earth. Oxygen is also a product of the chemical reaction plants use to create food, photosynthesis.
As well as biological reactions, Oxygen is also essential for combustion. Combustion, also known as burning, has been used for thousands of years to provide heat to humans. Combustion of fossil fuels is used for transportation. Oxygen is also used in medicine to treat people who have breathing difficulties, and recreationally for divers and submariners.
Cornelius Drebbel found that when heating potassium nitrate a gas was released, but he didn’t identify it as oxygen. The Swedish chemist Carl Wilhelm Scheele and British clergyman Joseph Priestley are both credited with discovering oxygen.
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