You’re breathing right now and your body is taking in oxygen (O) molecules. You need oxygen to survive, as do almost all other living organisms. It’s a good thing that oxygen makes up over twenty percent of the Earth’s atmosphere. We are the only planet in the solar system with enough oxygen gas available to let us survive.
Atomic Number: 8
Atomic Weight: 15.9994
Melting Point: 54.36 K (-218.79°C or -361.82°F)
Boiling Point: 90.20 K (-182.95°C or -297.31°F)
Density: 0.001429 grams per cubic centimeter
Phase at Room Temperature: Gas
Element Classification: Non-metal
Period Number: 2
Group Number: 16
Group Name: Chalcogen
Oxygen is a highly reactive element and is capable of combining with most other elements. It is required by most living organisms and for most forms of combustion. Impurities in molten pig iron are burned away with streams of high pressure oxygen to produce steel. Oxygen can also be combined with acetylene (C2H2) to produce an extremely hot flame used for welding. Liquid oxygen, when combined with liquid hydrogen, makes an excellent rocket fuel. Ozone (O3) forms a thin, protective layer around the earth that shields the surface from the sun’s ultraviolet radiation. Oxygen is also a component of hundreds of thousands of organic compounds.
Medical use of Oxygen
Oxygen therapy, also known as supplemental oxygen, is the use of oxygen as a medical treatment. This can include for low blood oxygen, carbon monoxide toxicity, cluster headaches, and to maintain enough oxygen while inhaled anesthetics are given. Long-term oxygen is often useful in people with chronically low oxygen such as from severe COPD or cystic fibrosis. Oxygen can be given in a number of ways including nasal cannula, face mask, and inside a hyperbaric chamber.
Oxygen is often prescribed for people with breathlessness, in the setting of end-stage cardiac or respiratory failure, advanced cancer or neurodegenerative disease, despite having relatively normal blood oxygen levels. A 2010 trial of 239 subjects found no significant difference in reducing breathlessness between oxygen and air delivered in the same way.
There are no absolute contraindications to the use of oxygen but the inspired concentration should be limited in the case of premature infants and those patients with chronic bronchitis and emphysema. However guidelines have been published by the British Thoracic Society (BTS) on the safe therapeutic use of medical oxygen, which encourages proper assessment of the patient before use. Compressed medical oxygen toxicity may manifest itself in the following ways:
- retrolenticular fibroplasia in premature infants exposed to oxygen concentrations greater than 40%
- convulsions appear after a few hours exposure to medical oxygen at pressures above 3bar(g)
- retrosternal soreness associated with coughing and breathing difficulties, made worse by smoking and exposure to cold air after breathing pure medical oxygen at atmospheric pressure for several hours.