Топ-100

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Krypton

Krypton is a noble gas which means it does not react with many other elements. It is clear and has no taste or smell. The atmosphere is only about one millionth part krypton. The name kypton comes from the Greek word kryptos meaning hidden. It is ...

                                               

Krypton difluoride

Krypton difluoride is a chemical compound, made of krypton and fluorine. The compound is chemically unstable. It will break into its components within a few days. Kryptondifluoride reacts with an explosion when it comes in contact with water or w ...

                                               

Lactose

Lactose is a disaccharide that consists of galactose and glucose molecules. Lactose makes up around 2-8% of the solids in milk. The name comes from the Latin word for milk, plus the -ose ending used to name sugars. Lactose is found in milk products.

                                               

Law of definite composition

The law of definite proportions states that a chemical compound always has exactly the same proportion of elements by mass. Amounting to the same thing is the law of constant composition. This states that all samples of a given chemical compound ...

                                               

Lawrencium

Lawrencium is a chemical element. It is also named eka-lutetium by some people. It has the symbol Lr. It has the atomic number 103. It is a radioactive element that does not exist in nature. It has to be made. Lawrencium is made from californium. ...

                                               

Lead

Lead is a chemical element. Its chemical symbol is Pb, which comes from plumbum, the Latin word for lead. Its atomic number is 82, atomic mass is 207.2 and has a melting point of 327.8°C. It is a very poisonous and heavy metal.

                                               

Lead nitrate

Lead nitrate is a chemical compound. It has lead and nitrate ions in it. It was known long ago as plumb dulcis. The lead is in the 2 oxidation state.

                                               

Leaving group

In chemistry, a leaving group is an atom or molecule that leaves another molecule during a reaction. This reaction can be for example a nucleophilic substitution. In this case the leaving group gets a pair of electrons. Some leaving groups are be ...

                                               

Lindane

Lindane is an insecticide. It can be used to kill insects. The European Union allows its use as an insecticide since 2008. This is because it takes a very long time to decay. Checks are now getting done to see how bad to humans it really is. It c ...

                                               

Liquid nitrogen

Liquid nitrogen is nitrogen at a very low temperature. It is usually produced by a process known as fractional distillation of air. At atmospheric pressure nitrogen boils at −196 °C. Nitrogen was first made into a liquid at Jagiellonian Universit ...

                                               

List of Hunds rules

In atomic physics, Hunds rules are rules that determine how the electrons in an atom work. Often, the first rule of Hunds rules is most often mentioned. The first rule of Hunds rules is so important in chemistry that it is simply just called Hund ...

                                               

Lithium aluminium hydride

Lithium aluminium hydride is an inorganic compound. Its chemical formula is LiAlH 4. It is commonly abbreviated as LAH. It is a grey solid. It was discovered by Finholt, Bond and Schlesinger in 1947.

                                               

Lithium bis(trimethylsilyl)amide

Lithium bisamide is a lithiated organosilicon compound. Its chemical formula is LiN 2. It is commonly abbreviated as LiHMDS which means lithium h exa m ethyl d i s ilazide. It is mainly used as a strong non-nucleophilic base and as a ligand.

                                               

Lithium cobalt oxide

Lithium cobalt oxide is a chemical compound. Its chemical formula is LiCoO 2. It is sometimes called lithium cobaltate or lithium cobaltite. Lithium cobalt oxide is a dark blue or bluish-gray crystalline solid. It is commonly used in the positive ...

                                               

Macromolecule

A macromolecule is a molecule with a large number of atoms. The word is usually used only when describing polymers, molecules which are made up of smaller molecules called monomers. All organic monomers are based on carbon, usually with hydrogen, ...

                                               

Magnesium

Magnesium is a chemical element with the symbol Mg, atomic number 12 and common oxidation state 2. It is an alkaline earth metal and the eighth most abundant element in the Earths crust, where it constitutes about 2% by mass, and ninth in the kno ...

                                               

Manganese(II) sulfate

Manganese sulfate, also known as manganous sulfate, is a chemical compound. It contains manganese in its 2 oxidation state. It contains manganese and sulfate ions. Its chemical formula is MnSO 4. It is a pink crystalline solid. It normally is bon ...

                                               

Manganese(III) fluoride

Manganese fluoride, also known as manganese trifluoride, is a chemical compound. It contains manganese and fluoride ions. The manganese ions are in the 3 oxidation state. Its chemical formula is MnF 3. It is a purple-pink powder. It is used to ad ...

                                               

Manganese(VII) oxide

Manganese oxide, also known as permanganic acid and manganese heptoxide, is a chemical compound. The manganese is in its 7 oxidation state. Its chemical formula is Mn 2 O 7. This is about the only 7 oxidation state compound of manganese that is n ...

                                               

Mass spectrometry

Mass spectrometry is a process that measures the mass-to-charge ratio of charged particles. You can use it to find out the mass of particles, and to find the basic chemicals in a sample or molecule. It can also tell you the chemical structures of ...

                                               

Meitnerium

Meitnerium is a chemical element in the periodic table. Its atomic number is 109. It is not found on earth naturally. Because of this, it needs to be made in a science laboratory. Its half life, or the amount of time it takes for half of the elem ...

                                               

Menthol

Menthol is an organic compound. It is gotten from the oils of corn mint, peppermint, or other mints. It can also be made artificially. It is a waxy, crystalline substance. It is white in color. It is a solid at room temperature. It melts at a tem ...

                                               

Mercury(I) iodide

Mercury iodide, also known as mercurous iodide, is a chemical compound. Its chemical formula is Hg 2 I 2. It has mercury and iodide ions in it. The mercury is in its 1 oxidation state.

                                               

Metallic hydrogen

Metallic hydrogen is an alkali metal made from hydrogen gas. This is formed when the hydrogen gas is under compression and results with the gas changing phase. It is an example of degenerate matter. The matter has a crystal structure of proton at ...

                                               

Mining

Explosives that explode when they are hit are also called mine, Two common types are Land mines and Naval mines. Mining is the process of digging things out of the ground. Any material that cannot be grown must be mined. Mining things from the gr ...

                                               

Mirex

Mirex is a chlorinated hydrocarbon that was commercialized as an insecticide. It was later banned because it was harmful to the environment. This white crystalline odorless solid is a derivative of cyclopentadiene. It was popularized to control f ...

                                               

Molar concentration

Molar concentration, or molarity, or simply concentration, is a term in physical chemistry. It measures the concentration of a solution or mixture. In chemistry, the molar concentration, c i {\displaystyle c_{i}} is defined as the amount of a con ...

                                               

Molar heat capacity

The molar heat capacity of a substance is the energy needed to raise the temperature of one mole of it by one degree Celsius. When using SI units, it can be calculated with the equation where c n {\displaystyle c_{n}} refers to the molar heat cap ...

                                               

Molar mass

Molar mass is the mass of a substance that has 6.022 × 10 23 atoms. The mass number of an element is equal to the molar mass of the element. The molar mass of a chemical compound is the mass when the compound has 6.022 × 10 23 molecules. Molar ma ...

                                               

Molecular geometry

Molecular geometry is the way atoms are arranged in a molecule. The three-dimensional arrangement determines many properties of that molecule. There are many different molecular structures. They are organised by the number of atoms involved and t ...

                                               

Molybdenum

Molybdenum is a chemical element. It has the chemical symbol Mo. It has the atomic number 42. It has 35 isotopes. The name Molybdenum is from the Greek meaning "leadlike". The color of pure molybdenum is silvery-white. It does not occur naturally ...

                                               

Naphthalene

Naphthalene is a crystalline, white hydrocarbon, with a strong smell. It is best known as the main ingredient in mothballs, urinal deodorizer blocks, and can be used as an antiseptic. In mothballs, it is used as an insecticide or pesticide. Napht ...

                                               

Neon

Neon is a noble gas. It is chemical element 10 on the periodic table. Its symbol is Ne. The word "neon" comes from the Greek word meaning "new". It was discovered by William Ramsay and Morris W. Travers in 1898. Neon does not react with other ele ...

                                               

Nicotine

Nicotine is a drug in tobacco cigarettes, cigars, pipe tobacco, chewing tobacco, vaping liquids and some e-cigarettes. Nicotine is an addictive stimulant that causes the heart to beat faster and makes blood pressure rise. It can also make a perso ...

                                               

Nihonium

Nihonium is a chemical element. It is also named eka-thallium. It has the symbol Nh. It has the atomic number 113. It is a transuranium element.The name nihonium from Japan"s name nihonニホン. Nihonium does not exist in nature, but is artificial. ...

                                               

Niobium

Niobium is a chemical element. It is sometimes named columbium. It has the chemical symbol Nb. It has the atomic number 41. It is a rare metal. Niobium is soft and grey. It is ductile. In chemistry it is placed in a group of metal elements named ...

                                               

Nitrate

Nitrate is a polyatomic ion. It is made up of one nitrogen and three oxygen atoms. It is part of many important molecules. Potassium nitrate is a common type of nitrate. It is often used in fertilizers because plants need both potassium and nitra ...

                                               

Nitric acid

Nitric Acid is a very corrosive and toxic strong acid that can cause severe burns. It is also known as aqua fortis. Nitric Acid is used in rocket fuels, to help make wood look older, and is used in explosives. It can react with metals such as cop ...

                                               

Nitride

In chemistry, a nitride is a compound of nitrogen with a less electronegative element, attached together in a specific way. Nitrides are a large class of compounds with a wide range of properties and applications. Most of the names for nitrides f ...

                                               

Nitro compound

A nitro compound is a molecule that has the nitro group. The nitro group is made of one nitrogen atom connected with two oxygen atoms. The nitrogen is also bonded to the rest of the molecule. Nitrogen normally has only three bonds. In a nitro gro ...

                                               

Nitrous oxide

Nitrous oxide is a gas with the chemical formula N 2 O. It is found naturally in the air. It is also made artificially, because it has many uses. It is a strong greenhouse gas, almost 300 times more so, per molecule, than carbon dioxide) and abou ...

                                               

Nonmetal

Nonmetal s or non-metal s are chemical elements that does not have the properties of a metal. Some are gases including: hydrogen, helium, oxygen, nitrogen, fluorine, neon or radon and many others. An example of a solid that is a nonmetal is sulfu ...

                                               

Novichok

The name Novichok is used for a number of chemical compounds that have been used as nerve agents from the 1970s to at least the 1990s in the Soviet Union. There are 3–5 different substances, all called Novichok. The exact formula of these agents ...

                                               

Oligosaccharide

An oligosaccharide is a polymer of a few different simple sugars. Oligosacchardides are carbohydrates. When they are hydrolized, oligosaccharides give 2 to 9 monosaccharides. Oligosacharides are formed when 2 to 9 monosaccharide units combine wit ...

                                               

Organic reaction

Organic reactions are chemical reactions involving organic compounds. The basic organic chemistry reaction types are addition reactions, elimination reactions, substitution reactions, pericyclic reactions, rearrangement reactions, photochemical r ...

                                               

Organolithium reagent

Organolithium compounds contain a direct bond between a carbon atom and a lithium atom. They are an important class of organometallic compound. The bonding between the carbon and lithium is highly polar due to the difference in electronegativity ...

                                               

Osmium

Osmium is a chemical element. It is element number 76 on the periodic table. Its symbol is Os. There is not much osmium on earth. There is actually such a small amount that osmium is very expensive. Osmium is a metal and it does not react very mu ...

                                               

Ostwald process

The Ostwald process is a chemical process for making nitric acid. The Ostwald process provides the main raw material for the most common type of fertilizer production. It is closely associated with the Haber process. It is named after Wilhelm Ost ...

                                               

Oxide

An oxide is a chemical compound containing at least one oxygen atom and at least one atom of one other element. Most of the Earths crust consists of oxides. Oxides can be made when elements are oxidized by air. Some common oxides are: Silicon dio ...

                                               

Pewter

Pewter is an alloy made of tin mixed with antimony and copper. It is soft and flexible and it can be melted easily. It dissolves in hydrochloric acid to produce tin chloride, leaving the antimony and copper behind in the hydrochloric acid. A long ...

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