Uses of Oxygen

Oxygen being the most widely occurring element on Earth, is a colorless, odorless, and tasteless gas. It is an active, life-sustaining component of the atmosphere, constituting nearly 23% of volume of the air we breathe. Being one of the most abundant element on the Earth, oxygen comprises about 90% of water, two-thirds of the human body and one fifth by volume of air. It is naturally found in the Sun and plays a vital role in the stellar carbon cycle. Oxygen is also dissolved in rivers, lakes, and oceans and in its molecular form oxygen can found almost anywhere in the atmosphere. Commercially, it can be prepared by the process of liquefaction and fractional distillation of air and through electrolysis of water. Now, let us see the different uses oxygen has in everyday life, to find out the importance of this element.

Oxygen Chemical Properties

Being the first member of group 16 of the periodic table, oxygen is chemically active, forming compounds with nearly all of elements except the inert gases. It is denser than air and can be dissolved in water up to certain extend. Although it is a poor conductor of heat and electricity, oxygen supports combustion but does not burn itself in the reaction. The natural oxygen in the atmosphere, called diatomic gas O₂ has a molecular weight 31.9988 while ozone O ₃, which is more reactive than natural oxygen, is another allotrope of oxygen formed due to electrical discharges or ultraviolet light reacting with the atmospheric oxygen.

It is paramagnetic in all its three forms i.e. solid, liquid and gaseous. Oxygen combines directly with various elements to form oxides and forms an important constituent of many acids, hydroxides and various other compounds. When cooled below its boiling point, oxygen turns in to a pale blue liquid and when cooled even more, the liquid solidifies, while retaining its color.

Uses of Oxygen

The uses of oxygen in everyday life can be classified into four major categories: metallurgy, rocketry, chemical synthesis, and medicine. Following are some common uses related to these categories.

• All living organisms including animals and plants use oxygen present in the air for respiration, also termed as aerobic respiration. It is a process in which food is burned in living cells in presence of oxygen to release energy for all metabolic activities. Besides this lifesaving process, medical oxygen uses in the body involve supply of oxygen packed in cylinders to aid people finding difficulty in breathing due to inadequate amount of oxygen, for example patients in hospitals, mountaineers at high latitudes, under water divers, astronauts walking in space, etc.
• Atmospheric oxygen O₂ is used for combustion of produce energy in automobiles, airplanes, ships, generators, industrial process, etc. Liquid oxygen uses include burning of fuel in spacecrafts for generating the required thrust in space where there is neither air nor oxygen.
• Oxygen uses in industry mainly involves melting, welding and cutting of metals. In oxy-acetylene and oxy-hydrogen blow torches, oxygen is used for producing very high temperatures somewhere around 3000º C and 2800º C respectively, to melt metals. During welding, the two metal pieces are brought close to each other, and the high temperature flame is applied at the junction to melt the metals. When the flame is removed, the metal pieces combine and later solidify to join together. While cutting a metal in to two parts, the flame is applied to one part until it turns red hot. Then the concentration or amount of oxygen is increased which oxidizes the red hot part of the metal, and the oxide being very brittle or soft, can be broken apart by hitting it with a hammer.
• Other uses involve production of iron and steel in blast furnaces using hot oxygen air. Even in mines, it is employed as a part of explosives for blasting rocks.
• In various chemical industries, oxygen is used in the manufacture of nitric acid, sulfuric acid, and other compounds and acids. Oxygen in its most reactive form, i.e. ozone O₃ is used in different chemical reactions to improve the rate of reaction and to ensure the fullest possible oxidation of undesired compounds.

Hence, whether it is steel making, metal refining, pharmaceuticals, petroleum processing, glass and ceramic manufacturing, pulp and paper manufacturing or health care, uses of oxygen are numerous. Apart from these, oxygen is also used for environmental protection in municipal and industrial effluent treatment plants and facilities.