Oxygen is an odorless, colorless, tasteless, and magnetic gaseous element which is a major component of the Earth's atmosphere. It is the second most common component that can be found on Earth. But aside from Earth, it is also present throughout the universe and is usually covalently bonded with other elements. In the periodic table, oxygen has the symbol O and atomic number of 8. Oxygen was first discovered in the late 16th century by a Polish alchemist and philosopher named Michael Sedziwoj. But the discovery of oxygen was not given much credit until Joseph Priestley published his discoveries in 1775. He called oxygen the 'dephlogisticated air.' Later in 1777, oxygen was independently discovered by a Swedish chemist named Carl Wilhelm Scheele. It was later shown as an elemental gas by Antoine Laurent Lavoisier, a French chemist. Oxygen in gaseous state can turn into liquid oxygen which is extremely cold and is pale blue in color. When this liquid oxygen is compressed, it can turn into solid oxygen, which is also pale blue. This has an atomic weight of 15.9994 and a density of 1.429 g per liter at 0 degrees Celsius. At atmospheric pressure, the boiling point is reached at -182.6 degrees Celsius and the melting point is at 218.4 degrees Celsius. Oxygen comprises 23.15 percent by weight and 20.947 percent by volume of the atmosphere, 46.7 percent of the Earth's solid crust and 85.8 percent by weight of the oceans. It comprises 60 percent of the human body which is a vital requirement in order to maintain life for all humans and almost all animals and plants also require oxygen in order to survive. Oxygen has many different uses. One of the most common uses is for patients with impaired breathing. Oxygen is administered to patients who find difficulty breathing especially during major surgical operations. Aside from this, oxygen is also used by people who are into aircraft flying. In high altitudes, there is poor oxygen concentration so people need this to support normal respiration. Oxygen is vital not only to the Earth's surface, but also to humans and other living organisms. Without oxygen, life could not be possible. |
