Oxygen was first discovered by Michał Sędziwój, Polish alchemist and philosopher in late 16th century. Sędziwój assumed the existence of oxygen by warming nitre (saltpeter). He thought of the gas given off as "the elixir of life". Oxygen was again discovered by the Swedish pharmacist Carl Wilhelm Scheele sometime before 1773, but the discovery was not published until after the independent discovery by Joseph Priestley on August 1, 1774, who called the gas dephlogisticated air (see phlogiston theory). Priestley published hi ...

See also:

Oxygen, Oxygen - Characteristics, Oxygen - Applications, Oxygen - History, Oxygen - Occurrence, Oxygen - Compounds, Oxygen - Isotopes, Oxygen - Precautions

Read more here: » Oxygen: Encyclopedia II - Oxygen - History

See also:

Chemical oxygen demand, Chemical oxygen demand - Overview, Chemical oxygen demand - History, Chemical oxygen demand - Using potassium dichromate, Chemical oxygen demand - Blanks, Chemical oxygen demand - Measurement of excess, Chemical oxygen demand - Calculations, Chemical oxygen demand - Inorganic interference, Chemical oxygen demand - Government regulation

Read more here: » Chemical oxygen demand: Encyclopedia II - Chemical oxygen demand - History

Liquid oxygen finds use as an oxidizer in rocket propulsion. Oxygen is essential to respiration, so oxygen supplementation has found use in medicine (as oxygen therapy). People who climb mountains or fly in airplanes sometimes have supplemental oxygen supplies (as air). Oxygen is used in welding (such as the oxyacetylene torch), and in the making of steel and methanol. Oxygen presents two absorption bands centered in the wavelengths 687 and 760 nanometers. Some scientists have proposed to use the measurement of the radiance coming fro ...

See also:

Oxygen, Oxygen - Characteristics, Oxygen - Applications, Oxygen - History, Oxygen - Occurrence, Oxygen - Compounds, Oxygen - Isotopes, Oxygen - Precautions

Read more here: » Oxygen: Encyclopedia II - Oxygen - Applications

Oxygen is a chemical element in the periodic table. It has the symbol O and atomic number 8. The element is very common, found not only on Earth but throughout the universe, usually covalently bonded with other elements. Unbound oxygen (usually called molecular oxygen, O2, a diatomic molecule) first appeared on Earth during the Paleoproterozoic era (between 2500 million years ago and 1600 million years ago) and as a product of the metabolic action of early anaerobes (archaea and bacteria). The presence of free oxygen ...

Including:

• Oxygen - Characteristics
• Oxygen - Applications
• Oxygen - History
• Oxygen - Occurrence
• Oxygen - Compounds
• Oxygen - Isotopes
• Oxygen - Precautions

Read more here: » Oxygen: Encyclopedia - Oxygen

In environmental chemistry, the chemical oxygen demand (COD) test is commonly used to indirectly measure the amount of organic compounds in water. Most applications of COD determine the amount of organic pollutants found in surface water (e.g. lakes and rivers), making COD a useful measure of water quality. It is expressed in millgrams per liter (mg/L), which indicates the mass of oxygen consumed per liter of solution. Older references may express the units as parts per million (ppm). Chemical oxygen demand - Over ...

Including:

• Chemical oxygen demand - Overview
• Chemical oxygen demand - History
• Chemical oxygen demand - Using potassium dichromate
• Chemical oxygen demand - Blanks
• Chemical oxygen demand - Measurement of excess
• Chemical oxygen demand - Calculations
• Chemical oxygen demand - Inorganic interference
• Chemical oxygen demand - Government regulation

Read more here: » Chemical oxygen demand: Encyclopedia - Chemical oxygen demand

Artificial respiration is a technique for providing air for a person who is not breathing on their own but whose heart is still beating. The provider breathes into the other person's lungs, preferably with the assistance of a barrier device. Artificial respiration is part of performing cardiopulmonary resuscitation (CPR) but is also performed separately, especially in near-drowning and similar situation ...

Including:

• Artificial respiration - Insufflations
• Artificial respiration - Oxygen
• Artificial respiration - History

Read more here: » Artificial respiration: Encyclopedia - Artificial respiration

Air-Independent Propulsion (AIP), is a term that encompasses technologies which allow a submarine to operate without the need to surface or use a snorkel to access atmospheric oxygen. The term usually excludes the use of nuclear power, and describes augmenting or replacing the diesel-electric propulsion system of non-nuclear vessels. AIP is usually implemented as an auxiliary source. Most such systems generate electricity which in turn drives an electric motor for propulsion or recharging the boat's batteries. The submarine's e ...

Including:

• Air-independent propulsion - Internal oxygen supply
• Air-independent propulsion - History
• Air-independent propulsion - Closed cycle diesel engines
• Air-independent propulsion - Closed cycle steam turbines
• Air-independent propulsion - Stirling cycle engines
• Air-independent propulsion - Fuel cells
• Air-independent propulsion - Nuclear power
• Air-independent propulsion - Production Non-Nuclear AIP Submarines

Read more here: » Air-independent propulsion: Encyclopedia - Air-independent propulsion

Gasoline is a petroleum-derived liquid mixture consisting primarily of hydrocarbons, used as fuel in internal combustion engines. Gasoline - Chemical analysis and production. Gasoline is produced in oil refineries. These days, material that is simply separated from crude oil via distillation, called natural gasoline, will not meet the required specifications (in particular octane rating; see below) for modern engines, but these streams will form part of the blend. The bulk of a typical gasoline consi ...

Including:

• Gasoline - Chemical analysis and production
• Gasoline - Volatility
• Gasoline - Octane rating
• Gasoline - Dangers
• Gasoline - Energy content
• Gasoline - Additives
• Gasoline - Lead
• Gasoline - MMT
• Gasoline - Oxygenate blending
• Gasoline - History
• Gasoline - Pharmaceutical
• Gasoline - Etymology
• Gasoline - World War II and octane
• Gasoline - Current use
• Gasoline - Stability

Read more here: » Gasoline: Encyclopedia - Gasoline

The Bessemer process was the first inexpensive industrial process for the mass-production of steel from molten pig iron. The process is named after its inventor, Henry Bessemer, who took out a patent on the process in 1855. The process is a development of a practice known in China as early as the 200s. The key principle is removal of impurities from the iron by oxidation through air being blown through the molten iron. The oxidation also raises the temperature of the iron mass and keeps it molten. Bessemer process - Bess ...

Including:

• Bessemer process - Bessemer converter
• Bessemer process - Predecessor processes
• Bessemer process - History
• Bessemer process - Importance
• Bessemer process - Obsolesence

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A heart-lung machine (HLM) is a device that temporarily takes over the function of the lungs and heart. It is sometimes also called cardiac bypass pump, in reference to its use in coronary artery bypass surgery, and cardiac pump. They are operated by allied health professionals known as perfusionists. Heart-lung machine - Uses of the heart-lung machine. Heart-lung machines are frequently used in heart surgery because it is difficult or even impossible to operate on the beating heart.

• Heart-lung machine - Uses of the heart-lung machine
• Heart-lung machine - Surgeries in which heart-lung machines are used
• Heart-lung machine - Components of a heart-lung machine
• Heart-lung machine - Pump
• Heart-lung machine - Oxygenator
• Heart-lung machine - History

Read more here: » Heart-lung machine: Encyclopedia - Heart-lung machine

Carbon-12 is the more abundant (98.89%) of the two stable isotopes of the element carbon. It contains 6 protons, 6 neutrons and 6 electrons. Carbon-12 is of particular importance as it is used as the standard from which all other isotopes' atomic weight is measured and thus the measurement of Avogadro's number. Carbon-12 - History. Prior to 1959 both the IUPAP and IUPAC tended to use used oxygen to define the mole, the chemists defining the mole as the number of atoms of oxygen which had mass ...

Including:

• Carbon-12 - History

Read more here: » Carbon-12: Encyclopedia - Carbon-12

In chemistry, to bleach something generally means to whiten it or oxidize it. A bleach is a chemical that can produce these effects. Common chemical bleaches include sodium hypochlorite, or "chlorine bleach," and "oxygen bleach," which contains hydrogen peroxide or a peroxide-releasing compound (eg. sodium perborate, or sodium percarbonate). "Bleaching powder" is calcium hypochlorite. Bleaching can be ...

Including:

• Bleach - History
• Bleach - Hazards

Read more here: » Bleach: Encyclopedia - Bleach

Carbon monoxide, chemical formula CO, is a colourless, odourless, tasteless, flammable and highly toxic gas. It is a major product of the incomplete combustion of carbon and carbon-containing compounds. It is less dense than air under ordinary conditions. It is very slightly soluble in water and burns in air with a characteristic blue flame, producing carbon dioxide; it is a component of producer gas and water gas, which are widely used artificial fuels. It is a reducing agent, removing oxygen from many compounds and is used in the re ...

Including:

• Carbon monoxide - Toxicity
• Carbon monoxide - History
• Carbon monoxide - Chemistry
• Carbon monoxide - Carbon monoxide in the atmosphere

Read more here: » Carbon monoxide: Encyclopedia - Carbon monoxide

A white dwarf is an astronomical object which is produced when a low or medium mass star dies. These stars are not heavy enough to generate the core temperatures required to fuse carbon in nucleosynthesis reactions, and after they have become a red giant during their helium-burning phase, they will shed their outer layers to form a planetary nebula, leaving behind an inert core consisting mostly of carbon and oxygen. This core has no further source of energy, and so will gradually radiate away its energy and cool down. The core ...

Including:

• White dwarf - Formation
• White dwarf - Characteristics
• White dwarf - History of discoveries

Read more here: » White dwarf: Encyclopedia - White dwarf

Carbon dioxide is an atmospheric gas comprised of one carbon and two oxygen atoms. A very widely known chemical compound, it is frequently called by its formula CO2. In its solid state, it is commonly known as dry ice. Carbon dioxide derives from multiple sources including volcanic outgassing, the combustion of organic matter and respiration processes of living aerobic organisms. It is also produced by various microorganisms from fermentation and cellular respiration. Plants utilize carbon dioxide durin ...

Including:

• Carbon dioxide - Chemical and physical properties
• Carbon dioxide - Uses
• Carbon dioxide - Dry Ice
• Carbon dioxide - Uses
• Carbon dioxide - Handling
• Carbon dioxide - Biology
• Carbon dioxide - Atmosphere
• Carbon dioxide - Variation in the past
• Carbon dioxide - Oceans
• Carbon dioxide - History

Read more here: » Carbon dioxide: Encyclopedia - Carbon dioxide

Argon is a chemical element in the periodic table. It has the symbol Ar and atomic number 18. The third noble gas, in group 18, argon makes up about 1% of the Earth's atmosphere, making it the most common noble gas on Earth. Argon - Notable characteristics. Argon is 2.5 times as soluble in water as nitrogen which is approximately the same solubility as oxygen. This highly stable chemical element is colorless and odorless in both its liquid and gaseous forms. There are few known true che ...

Including:

• Argon - Notable characteristics
• Argon - Applications
• Argon - History
• Argon - Occurrence
• Argon - Compounds
• Argon - Isotopes

Read more here: » Argon: Encyclopedia - Argon

The citric acid cycle (also known as the tricarboxylic acid cycle, the TCA cycle, or the Krebs cycle) is a series of chemical reactions of central importance in all living cells that utilize oxygen as part of cellular respiration. In these aerobic organisms, the citric acid cycle is a metabolic pathway that forms part of the break down of carbohydrates, fats and proteins into carbon dioxide and water in order to generate energy. It is the second of three metabolic pathways that are involved in fuel molecule catabolism and ATP production, the o ...

Including:

• Citric acid cycle - History
• Citric acid cycle - Location of cycle and inputs and outputs
• Citric acid cycle - Regulation
• Citric acid cycle - Major metabolic pathways converging on the TCA cycle

Read more here: » Citric acid cycle: Encyclopedia - Citric acid cycle

Chromium is a chemical element in the periodic table that has the symbol Cr and atomic number 24. Chromium - Notable characteristics. Chromium is a steel-gray, lustrous, hard metal that takes a high polish, melts with difficulty, and tarnishes. The most common oxidation states of chromium are +2, +3, and +6, with +3 being the most stable. +4 and +5 are rare. Chromium compounds of oxidation state 6 are powerful oxidants. Chromium(0) is unstable in oxygen, immediately producing a thin oxi ...

Including:

• Chromium - Notable characteristics
• Chromium - Applications
• Chromium - History
• Chromium - Biological role
• Chromium - Occurrence
• Chromium - Compounds
• Chromium - Isotopes
• Chromium - Chromium and the quintuple bond
• Chromium - Precautions

Read more here: » Chromium: Encyclopedia - Chromium

Zinc (from German zink) is a chemical element in the periodic table that has the symbol Zn and atomic number 30. Zinc - Notable characteristics. Zinc is a moderately reactive metal that will combine with oxygen and other non-metals, and will react with dilute acids to release hydrogen. The one common oxidation state of zinc is +2. Zinc - Applications. Zinc is the fourth most common metal in use, trailing only iron, aluminium, and copper in annual production. ...

Including:

• Zinc - Notable characteristics
• Zinc - Applications
• Zinc - Popular misconceptions
• Zinc - History
• Zinc - Biological role
• Zinc - Food Sources
• Zinc - Zinc Deficiency
• Zinc - Zinc Toxicity
• Zinc - Psoriasis
• Zinc - Immune System
• Zinc - Abundance
• Zinc - Zinc production
• Zinc - Compounds
• Zinc - Isotopes
• Zinc - Precautions

Read more here: » Zinc: Encyclopedia - Zinc

Acid rain is defined as any type of precipitation with a pH of below 5.0. Normal rain has a pH which can range between 4.5 and 5.6 with an average value of 5.0. This natural acidity is caused by dissolved carbon dioxide dissociating to form weak carbonic acid. 'Acid rain' is caused by sulfur from volcanic venting or impurities in fossil fuels, and nitrogen from the air, combining with oxygen to form sulfur dioxide and nitrogen oxides. These diffuse into the atmosphere and react with water to form sulfuric and nitric acids which are so ...

Including:

• Acid rain - Origin
• Acid rain - Formation
• Acid rain - History
• Acid rain - Prevention Methods
• Acid rain - Effects of acid rain on soil biology

Read more here: » Acid rain: Encyclopedia - Acid rain