Oxygen discovery and its properties

Oxygen has the atomic number 8 and the symbol O. It is a chemical element. It is a highly reactive non-metal and an oxidising agent that readily forms oxides with most elements and other compounds. It belongs to the chalcogen group in the periodic table. After hydrogen and helium, oxygen is the most abundant element on Earth and the third most abundant element in the universe. Two atoms of the element join together at ordinary temperature and pressure to generate dioxygen, a colourless and odourless diatomic gas with the formula O2. Although the percentage of diatomic oxygen gas in the Earth’s atmosphere has fluctuated greatly over time, it today makes up 20.95 percent of the atmosphere. Over half of the Earth’s crust is made up of oxygen in the form of oxides. 

Discovery of oxygen: 

Carl Wilhelm Scheele, a Swedish chemist, discovered oxygen in 1772 by heating potassium nitrate, mercuric oxide, and a variety of other chemicals. Joseph Priestley, an English scientist, discovered oxygen by the heat breakdown of mercuric oxide in 1774 and published his discoveries the same year, three years before Scheele. In 1775–80, Antoine-Laurent Lavoisier, a French chemist, reinterpreted the role of oxygen in respiration and combustion, rejecting the previously accepted phlogiston theory; he noted the element’s tendency to form acids when combined with a variety of substances and named the element oxygen (oxygène) after the Greek words for “acid former.” 

Occurrence: 

One of the most prevalent elements on the planet is oxygen. Oxygen makes up 20.9 percent of the atmosphere, 45 percent of the Earth’s crust (in the form of oxide minerals), and practically all of the water on the planet (89 percent ). Sulphates, phosphates, carbonates, and oxides are just a few of the natural minerals that contain it. Furthermore, behind hydrogen and helium, it is the third most plentiful element in the universe. 

Symbol: 

Oxygen is represented by the chemical symbol O. Although minor amounts of ozone (O3), which is made up of three atoms of oxygen, are present in the atmosphere, oxygen is primarily found as molecules made up of two atoms (O2). 

Properties of oxygen: 

Physical properties of oxygen: 

1. Oxygen can be found in three different states: liquid, solid, and gas. 
2. The liquid and solid forms are both light blue. 
3. Oxygen gas, on the other hand, is colourless, odourless, and tasteless. 
4. At a temperature of 182.96 °C, oxygen transforms from a gas to a liquid, which can then be solidified or frozen at -218.4 °C. 
5. Diatomic oxygen, nascent oxygen, and ozone are the three allotropic forms. 

Chemical properties of oxygen: 

1. Oxygen is a highly reactive and paramagnetic element that can easily combine with other elements. 
2. The ability of oxygen to facilitate combustion is one of its most essential chemical features. 
3. At room temperature, oxygen can also interact with elements, resulting in the development of rust. 
4. The process of decomposition is an example of oxygen reacting with chemicals. 
5. The major by-products of decomposition are carbon dioxide and water. 

Natural abundance of oxygen: 

By volume, oxygen accounts for 21% of the atmosphere. This is halfway between 17 percent (below which unacclimatized persons have difficulty breathing) and 25 percent (above which many organic compounds are highly flammable). The element and its compounds account for 49.2 percent of the Earth’s crust by mass and nearly two-thirds of the human body. 

Uses of oxygen: 

Oxygen therapy: 

Oxygen treatment is one of the medical applications of oxygen. Because breathing requires the intake of oxygen from the air, oxygen supplementation is employed in medicine. Treatment not only raises oxygen levels in the patient’s blood, but it also reduces resistance to blood flow in many forms of sick lungs, reducing the heart’s workload. Emphysema, pneumonia, some cardiac illnesses (congestive heart failure), some disorders that induce elevated pulmonary artery pressure, and any disease that affects the body’s ability to take up and use gaseous oxygen are all treated with oxygen treatment. Treatments are adaptable enough to be used in hospitals, at the patient’s home, or via portable devices. Oxygen tents were originally common in oxygen supplementation, but they’ve generally been supplanted by oxygen masks or nasal cannulas in recent years. 

In space suits and scuba diving suits: 

Modern space suits, which surround their occupants with pressurised air, are one notable application of O2 as a low-pressure breathing gas. These devices employ virtually pure oxygen at a third of normal pressure, resulting in an O2 partial pressure in the blood that is normal. To keep spacesuits flexible, this trade-off of higher oxygen concentration for lower pressure is required. 

Scuba divers and submarines use artificially delivered oxygen as well, however they generally use normal pressure and/or oxygen-air mixtures. When diving at pressures higher than sea level, O2 is normally only used for rebreather, decompression, or emergency treatment at relatively shallow depths (less than 6 metres). To avoid oxygen toxicity, deeper diving necessitates a large dilution of O2 with other gases such as nitrogen or helium. Supplemental oxygen is sometimes carried by those who climb mountains or fly in non-pressurized fixed-wing aircraft. 

Conclusion: 

Because oxygen is a component of DNA and practically all other physiologically significant substances, it is necessary for all forms of life. The iron atom at the centre of haemoglobin in the blood picks up oxygen in the lungs and transports it to where it is needed. Every human being requires oxygen to breathe, yet, as with so many other things, too much of it is harmful. Lung injury can develop if a person is exposed to excessive levels of oxygen for an extended period of time.