wikidata.org
magnesium. Magnesium is a chemical element; it has symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point, and high chemical reactivity. Like the other alkaline earth metals, it occurs naturally only in combination with other elements and almost always has an oxidation state of +2. It reacts readily with air to form a thin passivation coating of magnesium oxide that inhibits further corrosion of the metal. The free metal burns with a brilliant-white light. The metal is obtained mainly by electrolysis of magnesium salts obtained from brine. It is less dense than aluminium and is used primarily as a component in strong and lightweight alloys that contain aluminium.
atm_gdb_ChemicalElementBusiness
wikidata.org 0 views · 1mo ago
aluminium. Aluminium or aluminum is a chemical element; it has symbol??Al and atomic number??13. It has a density lower than other common metals, about one-third that of steel. Aluminium has a great affinity toward oxygen, forming a protective layer of oxide on the surface when exposed to air. It visually resembles silver, both in its color and in its great ability to reflect light. It is soft, nonmagnetic, and ductile. It has one stable isotope, 27Al, which is highly abundant, making aluminium the 12th-most abundant element in the universe. The radioactivity of 26Al leads to it being used in radiometric dating.
atm_gdb_ChemicalElementBusiness
wikidata.org 0 views · 1mo ago
silicon. Silicon is a chemical element; it has symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic lustre, and is a tetravalent non-metal and semiconductor. It is a member of group 14 in the periodic table: carbon is above it; and germanium, tin, lead, and flerovium are below it. It is relatively unreactive. Silicon is a significant element that is essential for several physiological and metabolic processes in plants. Silicon is widely used as a semiconductor material in various electrical devices such as transistors, solar cells, and integrated circuits. It dominates semiconductor applications due to its low cost, excellent electronic properties, and adaptable physical characteristics.
atm_gdb_ChemicalElementBusiness
wikidata.org 0 views · 1mo ago
Earth mass. An Earth mass (denoted as M?, M??? or ME, where ? and ??? are the astronomical symbols for Earth), is a unit of mass equal to the mass of the planet Earth. The current best estimate for the mass of Earth is M? = 5.9722??1024??kg, with a relative uncertainty of 10???4. It is equivalent to an average density of 5515??kg/m3. Using the nearest metric prefix, the Earth mass is approximately six ronnagrams, or 6.0??Rg.
unit_gdb_UnitOfMass
wikidata.org 0 views · 1mo ago
Q1131660. The stone or stone weight is an English and British imperial unit of mass equal to 14 avoirdupois pounds (???6.35??kg). The stone continues in customary use in the United Kingdom and Ireland for body weight.
unit_gdb_UnitOfMass
wikidata.org 0 views · 1mo ago
kelvin. The kelvin is the base unit for temperature in the International System of Units (SI). The Kelvin scale is an absolute temperature scale that starts at the lowest possible temperature, taken to be 0??K. By definition, the units of the Celsius scale and the Kelvin scale have the same magnitude, and any temperature in degrees Celsius can be converted to the kelvin scale by adding 273.15.
unit_gdb_TemperatureUnitOfMeasure
wikidata.org 5 views · 1mo ago
degree Celsius. The degree Celsius is the unit of temperature on the Celsius temperature scale, one of two temperature scales used in the International System of Units (SI), the other being the closely related Kelvin scale. The degree Celsius can refer to a specific point on the Celsius temperature scale or to a difference or range between two temperatures. It is named after the Swedish astronomer Anders Celsius (1701???1744), who proposed the first version of it in 1742. The unit was called centigrade in several languages for many years. In 1948, the International Committee for Weights and Measures renamed it to honor Celsius and also to remove confusion with the term for one hundredth of a gradian in some languages. Most countries use this scale, with the exception of the United States, some island territories, and Liberia, where the Fahrenheit scale is still used.
unit_gdb_TemperatureUnitOfMeasure
wikidata.org 1 view · 1mo ago
degree Fahrenheit. The Fahrenheit scale is a temperature scale based on one proposed in 1724 by the physicist Daniel Gabriel Fahrenheit (1686???1736). It uses the degree Fahrenheit as the unit. Several accounts of how he originally defined his scale exist, but the original paper suggests the lower defining point, 0????F, was established as the freezing temperature of a solution of brine made from a mixture of water, ice, and ammonium chloride. The other limit established was his best estimate of the average human body temperature, originally set at 90????F, then 96????F.
unit_gdb_TemperatureUnitOfMeasure
wikidata.org 0 views · 1mo ago
Temperature
degree Rankine. temperature unit
unit_gdb_TemperatureUnitOfMeasure
wikidata.org 3 views · 1mo ago
hydrogen. Hydrogen is a chemical element; it has the symbol??H and atomic number??1. It is the lightest and most abundant chemical element in the universe, constituting about 75% of all normal matter. Under standard conditions, hydrogen is a gas of diatomic molecules with the formula??H2, called dihydrogen, or sometimes hydrogen gas, molecular hydrogen, or simply hydrogen. Dihydrogen is colorless, odorless, non-toxic, and highly combustible. Stars, including the Sun, mainly consist of hydrogen in a plasma state, while on Earth, hydrogen is found as the gas??H2 (dihydrogen) and in molecules, such as in water and organic compounds. The most common isotope of hydrogen, 1H, consists of one proton, one electron, and no neutrons.
atm_gdb_ChemicalElementBusiness
wikidata.org 1 view · 1mo ago
helium. Helium is a chemical element; it has symbol He and atomic number 2. It is a colorless, odorless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling point is the lowest among all the elements, and it does not have a melting point at standard pressures. It is the second-lightest and second-most abundant element in the observable universe, after hydrogen. It is present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this in both the Sun and Jupiter, because of the very high nuclear binding energy of helium-4 with respect to the next three elements after helium. This helium-4 binding energy also accounts for why it is a product of both nuclear fusion and radioactive decay. The most common isotope of helium in the universe is helium-4, the vast majority of which was formed during the Big Bang. Large amounts of new helium are created by nuclear fusion of hydrogen in s
atm_gdb_ChemicalElementBusiness
wikidata.org 0 views · 1mo ago
lithium. Lithium is a chemical element; it has symbol Li and atomic number??3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid element. Like all alkali metals, lithium is highly reactive and flammable, and must be stored in vacuum, inert atmosphere, or inert liquid such as purified kerosene or mineral oil. It exhibits a metallic luster when pure, but quickly corrodes in air to a dull silvery gray, then black tarnish. It does not occur freely in nature, but occurs mainly as pegmatitic minerals, which were once the main source of lithium. Due to its solubility as an ion, it is present in ocean water and is commonly obtained from brines. Lithium metal is isolated electrolytically from a mixture of lithium chloride and potassium chloride.
atm_gdb_ChemicalElementBusiness
wikidata.org 0 views · 1mo ago
beryllium. Beryllium is a chemical element; it has symbol Be and atomic number 4. It is a steel-gray, hard, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with other elements to form minerals. Gemstones high in beryllium include beryl and chrysoberyl. It is a relatively rare element in the universe, usually occurring as a product of the spallation of larger atomic nuclei that have collided with cosmic rays. Within the cores of stars, beryllium is depleted as it is fused into heavier elements. Beryllium constitutes about 0.0004 percent by mass of Earth's crust. The world's annual beryllium production of 220 tons is usually manufactured by extraction from the mineral beryl, a difficult process because beryllium bonds strongly to oxygen.
atm_gdb_ChemicalElementBusiness
wikidata.org 0 views · 1mo ago
pint. The pint is a unit of volume or capacity in both the imperial and United States customary measurement systems. In both of those systems, it is one-eighth of a gallon.
unit_gdb_UnitOfVolume
wikidata.org 1 view · 1mo ago
barrel. A barrel is one of several units of volume applied in various contexts: there are dry barrels; fluid barrels, such as the British beer barrel and American beer barrel; oil barrels, etc. For historical reasons, the volumes of some barrel units are roughly double the volumes of others; volumes in common use range approximately from 100 to 200 litres. In many connections, the term drum is used almost interchangeably with barrel.
unit_gdb_UnitOfVolume
wikidata.org 1 view · 1mo ago
bushel. A bushel is an imperial and US customary unit of volume, based upon an earlier measure of dry capacity. The old bushel was used mostly for agricultural products, such as wheat: in modern usage, the volume is nominal, with bushels denoting a mass defined differently for each commodity.
unit_gdb_UnitOfVolume
wikidata.org 1 view · 1mo ago
fluid ounce. A fluid ounce is a unit of volume typically used for measuring liquids. The British Imperial, the United States customary, and the United States food labeling fluid ounce are the three that are still in common use, although various definitions have been used throughout history.
unit_gdb_UnitOfVolume
wikidata.org 0 views · 1mo ago
Volume
gross register tonnage. Gross register tonnage, or gross registered tonnage, is a ship's total internal volume expressed in "register tons", each of which is equal to 100 cubic feet (2.83??m3). Replaced by Gross Tonnage (GT), gross register tonnage uses the total permanently enclosed capacity of the vessel as its basis for volume. Typically this is used for dockage fees, canal transit fees, and similar purposes where it is appropriate to charge based on the size of the entire vessel. Internationally, GRT may be abbreviated as BRT for the German "Bruttoregistertonne".
unit_gdb_UnitOfVolume
wikidata.org 1 view · 1mo ago
cord. The cord is a unit of measure of dry volume used to measure firewood and pulpwood in the United States and Canada.
unit_gdb_UnitOfVolume
wikidata.org 0 views · 1mo ago
ounce. The ounce is any of several different units of mass, weight, or volume and is derived almost unchanged from the uncia, an Ancient Roman unit of measurement.
unit_gdb_UnitOfMass
wikidata.org 0 views · 1mo ago
pound. The pound or pound-mass is a unit of mass used in both the British imperial and United States customary systems of measurement. Various definitions have been used; the most common today is the international avoirdupois pound, which is legally defined as exactly 0.45359237??kilograms, and which is divided into 16 avoirdupois ounces. The international standard symbol for the avoirdupois pound is lb; an alternative symbol is lbm, #, and ??? or ?????.
unit_gdb_UnitOfMass
wikidata.org 0 views · 1mo ago
carat. The carat (ct) is a unit of mass equal to 200??mg, which is used for measuring gemstones and pearls. The current definition, sometimes known as the metric carat, was adopted in 1907 at the Fourth General Conference on Weights and Measures, and soon afterwards in many countries around the world. The carat is divisible into 100 points of 2??mg. Other subdivisions, and slightly different mass values, have been used in the past in different locations.
unit_gdb_UnitOfMass
wikidata.org 0 views · 1mo ago
light-year. A light-year, alternatively spelled light year, is a unit of length used to express astronomical distances and is equal to exactly 9460730472580.8??km, which is approximately 9.46 trillion kilometres or 5.88 trillion miles. As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year. Despite its inclusion of the word "year", the term is not a unit of time.
unit_gdb_UnitOfLength
wikidata.org 0 views · 1mo ago
astronomical unit. The astronomical unit is a unit of length defined as 149597870700??m. Historically, the astronomical unit was conceived as the average Earth-Sun distance, before its modern redefinition in 2012.
unit_gdb_UnitOfLength
wikidata.org 1 view · 1mo ago
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