Oxygen
Oxygen and its compounds play a key role in many of the important processes of life and industry. Oxygen in the biosphere is essential in the processes of respiration and metabolism, the means by which animals derive the energy needed to sustain life. Furthermore, oxygen is the most abundant element at the surface of the Earth. In combined form it is found in ores, earths, rocks, and gemstones, as well as in all living organisms. Oxygen is a gaseous chemical element in
Group VA of the periodic table. The chemical symbol for atomic oxygen is O, its atomic number is 8, and its atomic weight is 15.9994. Elemental oxygen is known principally in the gaseous form as the diatomic molecule, which makes up 20.95% of the volume of dry air. Diatomic oxygen is colorless, odorless, and tasteless.
Two 18th-century scientists share the credit for first isolating elemental oxygen: Joseph PRIESTLEY (1733-1804), an English clergyman who was employed as a literary companion to Lord Shelburne at the time of his most significant experimental work, and Carl Wilhelm SCHEELE (1742-86), a Swedish pharmacist and chemist. It is generally believed that Scheele was the first to isolate oxygen, but that Priestley, who independently achieved the isolation of oxygen somewhat later, was the first to publicly announce his findings. The interpretation of the findings of Priestley and the resultant clarification of the nature of oxygen as an element was accomplished by the French scientist Antoine-Laurent
LAVOISIER (1743-94). Lavoisier's experimental work, which extended and improved upon Priestley's experiments, was principally responsible for the understanding of COMBUSTION and the establishment of the law of conservation of matter.
Lavoisier gave oxygen its name, which is derived from two Greek words that mean
"acid former." Lavoisier held the mistaken idea that oxides, when dissolved in water, would form only acids. It is true that some oxides when dissolved in water do form acids; for example, sulfur dioxide forms sulfurous acid. Some oxides, however, such as sodium oxide, dissolve in water to form bases, as in the reaction to form sodium hydroxide; therefore oxygen was actually inappropriately named.
NATURAL OCCURRENCE
Oxygen is formed by a number of nuclear processes that are believed to occur in stellar interiors. The most abundant isotope of oxygen, with mass 16,...
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... are observed to exist over a range of compositions all possessing the same underlying structure. A number of these titanium oxides exhibit more than one crystal structure (polymorphism). The most oxidized compound, titanium, is widely used in the RUTILE form as a white pigment in paints. Ternary oxides, consisting of two metallic elements plus oxygen, are of great interest to solid-state scientists. For example, compounds such as the SPINELS and the PEROVSKITES are studied extensively because of their interesting magnetic and electrical properties. Examples of important ternary oxides are the magnetic FERRITES, whose magnetic properties can be tailored, making them useful in computer memory units. The ferrites are prepared by firing compacted mixtures of iron oxide and one or more metal oxides (such as those of nickel, copper, zinc, magnesium, and manganese). Also of importance in inorganic chemistry are the oxides of the nonmetals. Most of the nonmetals are known to form a wide variety of compounds with oxygen. The nitrogen oxides are undesirable by-products of high-temperature combustion in air (as in an internal combustion engine) and can cause serious environmental pollution.
oxygen out of the blood and uses it in the body's cells. The cells use
Feldspar and Olivine are two silicate minerals commonly found on the Earth’s surface, their chemical formulas are KAlSi3O8 – NaAlSi3O8 –CaAl2Si2O8 for feldspars and (Mg, Fe)2SiO4 for olivine. Olivine is a nesosilicate, whereas feldspars are a group of tectosilicates, both minerals are anhydrous, since they contain no water in their chemical structure. Feldspars hold differing quantities of different elements, such as potassium, calcium, and sodium; making them classifiable in terms of composition, for instance, NaAlSi3O8 is Albite, while CaAl2Si2O8 is referred to as Anorthite.
The Effect of Light Intensity on the Rate of Oxygen Production in a Plant While Photosynthesis is Taking Place
The earth is made up of roughly 111 elements and combinations thereof, but only around 90 of the elements occur naturally. In 1789 Martin Klaproth discovered a new element and decided to name it after the newly discovered planet Uranus (Zoellner, 2009). This element called uranium is lithophilic and is the last natural element on the periodic table. It is the 92nd elements, containing 92 protons and an atomic mass of 238.0 grams (Cox, 1995). Uranium comes from the ores of uranite, canotite, and is present in only low concentrations of igneous rocks, such as granite. Uranium can also be seen in some glazes of pottery, as well as in the metals of armor-piercing weapons. This element also contains an extremely long half-life of over four billion years. This means that a majority of the uranium on earth today, is the exact same uranium that was present in the makings of the Earth (Cox, 1995; Thomson, 1963).
Oxygen is an essential component for cellular metabolic processes. As a result of normal cellular metabolism, oxidative products i.e. oxygen free radicals or reactive oxygen species are produced. In eukaryotic cells energy is generated in mitochondria as a result of aerobic respiration and this oxidative metabolism is responsible for formation of various compounds. Nearly all of these compounds are advantageous but a small proportion could be lethal if produced in higher concentration. During normal conditions small quantities of oxidative products are necessary for certain sub cellular events, including enzyme activation, formation of disulfide bond during the folding of new proteins, signal transduction and gene expression etc. (Yu etal., 2002; Droge, 2002). Oxidative stress can be defined as the excessive production of ROS which are not adequately removed from the body, because of reduced antioxidant defense system or the ROS increases beyond the capacity of antioxidants. The balance between oxidants and antioxidants is vital because oxidative stress can cause oxidative damages to N.A, lipids and proteins. The most important ROS are superoxide anion (O2−), singlet oxygen (O2), hydrogen peroxide (H2O2) and highly reactive hydroxyl radical (OH-). Whereas, antioxidant defense system is responsible to give protection against ROS. These antioxidants can scavenge and destroy ROS. The major antioxidant enzymes are catalase (CAT), superoxide dismutase (SOD) PON ….. and glutathione system (Sies, 1985; Valko et al., 2007; Halliwell and Gutteridge, 1990).
Herndon J. M, 2005, Current Science, Scientific Basis of Knowledge of Earth’s Composition, 88, 1034-1036)
I liked (-- removed HTML --) Diary Of An Oxygen Thief (-- removed HTML --) from the start to the end. The book started out compelling. The anonymous writer did very well and I wanted to keep reading to see if he would ever break his pact with himself to never have an alcoholic drink again. The writer faced many situations that he definitely could have avoided and not hurt other people's feelings. He taught himself and learned from his past experiences. I feel bad for him, because he had to make the mistakes first to even realize what harm he was doing to not only himself but everyone he dragged into his life.
Oxidation-reduction reactions can be used to stereochemically control and produce many different organic molecules. The oxidation step in this process increases the number of carbon oxygen bonds by losing a hydrogen and breaking that bond. Through the reduction step, carbon-oxygen bond is broken and the hydrogen is returned.
Previous page, Chalcopyrite ore (sulfide ore) that is made up of copper iron and sulfur (CuFeS2). Source:
One very important piece of information is that gemstones and crystals are grown during the cooling, formative stages of Earth’s development and so it has lead me to the conclusion that they are gifts from nature. According to physics, gemstones and crystals consist of natural balances and solid sta...
Carbon Dioxide is a colorless, odorless gas that occurs in small quantities in the earth's atmosphere naturally. The earth's ocean, soil, plants and animals release CO2. The formula of Carbon Dioxide is CO2. The CO2 molecule contains 2 oxygen atoms that each share 2 electrons with a carbon atom to form 2 carbon - oxygen double bonds. The atoms are arranged as so (OHT). This is called a 'linear molecule'.
Oxygen (O) is one of the most important ions present in the body, making up 61% of the body’s mass. It aids in the destruction of harmful bacteria, while preserving the bacteria that is beneficial for the body. Oxygen takes on its role, and transfers the bacteria absorbed into the lungs, to the cells, allowing for cell respiration. Oxygen allows for the replacement of old cells, protection of the new ones, production of energy from the food, and decomposition of other foods (“Oxygen and Human Body,” n.d.). Oxygen is also vital to produce an activity known as metabolism, which is ‘the sum of the physical and chemical processes in an organism by which its material substance is ...
The field of geology has many different branches. Some of these areas have hardly anything in common. The one thing that they all include, though, is that each one concentrates on some part of the Earth, its makeup, or that of other planets. Mineralogy, the study of minerals above the Earth and in its crust, is different from Petrology, the st...
Photosynthesis is the process in which living cells from plants and other organisms use sunlight to produce nutrients from carbon dioxide and water, the image below “Diagram of photosynthesis 1,” helps show this process. Photosynthesise generally creates oxygen as a by-product through the use of the green pigment, chlorophyll, found in the plant that helps this reaction occur. “Photosynthesis provides us with most of the oxygen we need in order to breathe. We, in turn, exhale the carbon dioxide needed by plants,” (factmonster,2017). This is able to show us why photosynthesis is so greatly needed to occur through plants in order to give one another essentials needed for continuity of life. “Plants perform photosynthesis because it generates the food and energy they need for growth and cellular respiration,” (photosynthesieeducation, 2016).