Топ-100

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Deuterium

Deuterium is an isotope of hydrogen, the first element. Deuterium has one proton and one neutron. Hydrogen does not have a neutron, only a proton. Another isotope of hydrogen, tritium, has two neutrons. The chemical symbol for Deuterium is 2 H bu ...

                                               

Dibutyl sebacate

Dibutyl sebacate is an organic compound. It is used as a plasticizer. It is a dibutyl ester of sebacic acid. Its main use is to produce plastics. It can make cellulose acetate butyrate, cellulose acetate propionate, ethyl cellulose, polyvinyl but ...

                                               

Dichlorphenolindophenol

DCPIP is a blue chemical used as a dye because when it is oxidized it is blue. Once DCPIP is reduced it does not have a color anymore. This reaction can be reversed, and the colourless DCPIP will turn blue again, when it is oxidized.

                                               

Dieldrin

Dieldrin is a chlorinated hydrocarbon originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide. Dieldrin is closely related to aldrin. Aldrin reacts further to form dieldrin. Aldrin is not toxic to insects, it is oxidized in the in ...

                                               

Diethyl ether

Diethyl ether is a clear liquid chemical. It is often just called ether. Ether burns very easily and boils at about 35°C. It has a sweet smell and does not mix with water. Ether was discovered in 1275. It was used in the past as a general anesthe ...

                                               

Dioxin

Dioxins is the name for a group of chemical compounds. These are organic compounds. Polychlorinated dibenzodioxins, or simply dioxins, are a group of halogenated organic compounds which are significant because they act as environmental pollutants ...

                                               

Disaccharide

A disaccharide is a sugar composed of two monosaccharides, such as glucose and fructose that make up the disaccharide sucrose. It is formed when two sugars are joined together and a molecule of water is removed. Due to this, disaccharides cannot ...

                                               

Distillation

Distillation is a process where a mixture made of two or more liquids with different boiling points can be separated from each other. The mixture is heated until one of the components boils. The vapor is then fed into a condenser, which cools the ...

                                               

Disulfur dichloride

Disulfur dichloride, also known as sulfur chloride, is a chemical compound. Its chemical formula is S 2 Cl 2. It contains sulfur in its 1 oxidation state. It contains chlorine in its -1 oxidation state.

                                               

Disulfur dinitride

Disulfur dinitride is a chemical compound. Its chemical formula is S 2 N 2. It contains sulfur in its 3 oxidation state. It also contains nitride ions.

                                               

Double bond

A double bond in chemistry is when two chemical elements are joined together in a chemical bond and share four bonding electrons instead of the usual two. The most common double bond is between two carbon atoms, and can be found in alkenes. There ...

                                               

Einsteinium

Einsteinium is a chemical element with the atomic number 99. That means an Einsteinium atom has 99 protons and 99 electrons. It is a synthetic element, so all isotopes are radioactive. Einsteinium belongs to the actinoids, and it is the 7th of th ...

                                               

Enantiomer

In chemistry, an enantiomer is a special kind of isomer. It is a molecule that looks exactly like another one when viewed in a mirror. The subject of mirror-image chemicals is known as chirality. If you try to put the two molecules on top of each ...

                                               

Endothermic reaction

An endothermic reaction is a chemical reaction that takes in energy from the surroundings. The opposite of an endothermic reaction is an exothermic reaction. Reversible reactions are where the products can react to remake the original reactants. ...

                                               

Epoxide

In organic chemistry, an epoxide is a molecule that has a ring with at least three atoms in total, two carbon atoms and one oxygen atom. These three atoms are bonded, or stuck together, in a small ring. The ring of atoms is shaped like a triangle ...

                                               

Fermium

Fermium is a chemical element. It has an atomic number of 100, which makes it at position 100 at the periodic table. Fermium cannot be found in nature, it has to be made. Scientists can create it by combining plutonium with neutrons at very high ...

                                               

Formaldehyde

Formaldehyde is a chemical compound. It is a colorless gas with a strong smell. It is flammable and toxic. It is the simplest aldehyde. Its main application is as a disinfectant. It is a biocide, this means it can kill most bacteria and fungi. It ...

                                               

Francium

Francium is a chemical element with the chemical symbol Fr and an atomic number of 87. It is a metal. In chemistry it is placed in a group of metal elements named the alkali metals. Francium is very radioactive. It is in very small amounts in ura ...

                                               

Fumigation

Fumigation is the making of toxic fumes. It may be done for several reasons. The most common use is to kill insects that hide in various places in a house or other building. There are a few steps to fumigate. First, the house or room is sealed. T ...

                                               

Gadolinium

Gadolinium is a chemical element. It has the chemical symbol Gd. It has the atomic number 64. It is part of a group of chemical elements in the periodic table named the Lanthanides. It is a rare earth element. It is silvery white, malleable and d ...

                                               

Glucose

Glucose is a simple carbohydrate, or sugar. It is one of several kinds of sugars. It is important because cells in an organism use it as a source of energy. Turning glucose into energy is called cellular respiration, which is done inside the cell ...

                                               

Group (periodic table)

A group is any column on the periodic table. Elements in the same group usually have similar properties, because they have the same number of electrons in the outermost electron shell. There are eight main groups of elements, numbered 1, 2, and 1 ...

                                               

Half-life (element)

This article is about the property of radioactive elements. For the video game, see Half-Life video game. The half-life of a substance is the time it takes for half of the substance to decay. The word "half-life" was first used when talking about ...

                                               

Haloalkane

Haloalkanes are alkanes that contain one or more halogens. A variety of different reactions can form these organic compounds. They cannot quickly be reacted, making them reasonably stable. There are many kinds of haloalkanes, used for many purpos ...

                                               

Halogen

The halogens are chemical elements under the second-to-right column in the periodic table, also known as Group 17. The elements in the group are fluorine, chlorine, bromine, iodine, astatine, and tennessine. Halogen literally means "salt becomer" ...

                                               

Helium-4

Helium-4 is an isotope of helium. It is the most common isotope of helium in the universe. Out of all the helium on the Earth, 99.99986% is helium-4. The nucleus of a helium-4 atom is also known as the alpha particle. Helium-4 is made of 2 proton ...

                                               

Hematite

Hematite or haematite is the main ore of iron. It is mostly iron oxide. Millions of tons are dug up every year. This is usually to feed to blast furnaces to make steel. It is a mineral related to corundum. It is an oxide. It has a metallic luster ...

                                               

Heptachlor

Heptachlor is an insecticide. It was used against ants, termites, against mosquitos of the genus Anopheles, that can spread malaria and as a general pesticide. In humans, heptachlor damages the liver, and the central nervous system. It may cause ...

                                               

Hexachlorobenzene

Hexachlorobenzene is an aromatic compound. The molecule structure resembles benzene, except that hydrogen atoms are replaced by chlorine. It is a colorless powder that is produced using catalysis from Iron chloride or from Hexachlorocyclohexane. ...

                                               

Homologous series

In chemistry, a homologous series is a series of chemical compounds with the same general formula. Usually these compounds vary by a single parameter such as the length of a carbon chain. Examples of such series are the straight-chained alkanes, ...

                                               

Hydrazone

A hydrazone is the functional group with structure R 1 R 2 C=NNH 2. They are like aldehydes or ketones, with an NNH 2 group instead of the oxygen atom. They are made by reacting hydrazines with ketones or aldehydes: Hydrazones are very useful mol ...

                                               

Hydrobromic acid

Hydrobromic acid is an acid. Its chemical formula is HBr. It is a very strong acid. It is used to make bromides by reaction with metals or metal oxides. It can be made by reacting bromine, sulfur dioxide, and water. This reaction makes hydrobromi ...

                                               

Hydrofluoric acid

Hydrofluoric acid is a solution of hydrogen fluoride in water. Its chemical formula is HF. It is a very dangerous acid, being very corrosive and extremely toxic. It can dissolve glass to make hexafluorosilicic acid. If it gets on the skin, it can ...

                                               

Hydrogen bond

A hydrogen bond is a low kind type of dipole-dipole bond that exists between an electronegative molecule and a hydrogen molecule bonded to another electronegative molecule. This type of bond always involves a hydrogen atom. That explains the name ...

                                               

Hydrogen chloride

Hydrogen chloride is a colorless irritating gas. It can dissolve in water to make hydrochloric acid. It was first prepared by Glauber. He called it spirit of salt.It reacts with ammonia to make a white smoke of ammonium chloride. It is used in th ...

                                               

Hydrogen halide

Hydrogen halides are inorganic compounds that contain a hydrogen ion and a halide ion. The halogens are fluorine, chlorine, bromine and iodine. Astatine does not make a stable hydrogen halide, so it is not included. The hydrogen halides are diato ...

                                               

Hydrogen iodide

Hydrogen iodide is a chemical compound. Its chemical formula is HI. It is a colorless odorous gas. It reacts with oxygen to make iodine and water. It can be made by reducing iodine with hydrazine. It can also be made by reacting iodides with non- ...

                                               

Hydrogen peroxide

Hydrogen peroxide is a chemical compound. Its molecular formula is H 2 O 2. It is used as a cleaner, and as hair bleach. In a concentration of 3%, it can be used to treat wounds. Over time it will slowly become oxygen gas and water through decomp ...

                                               

Hypochlorous acid

Hypochlorous acid is a chemical compound. Its chemical formula is HClO or HOCl. It is not stable. It contains chlorine in its 1 oxidation state. It is a powerful oxidizing agent. It is made by reacting sodium hypochlorite with an acid that cannot ...

                                               

Indium

Indium is a chemical element. It has the chemical symbol In. It has the atomic number 49. It is a rare metal. It is a soft, malleable and poor metal. Indium looks like zinc. Pieces of indium can easily be joined together by pushing one piece into ...

                                               

Inner transition metal

Inner transition metal s are chemical elements on the periodic table. They are normally shown in two rows below all the other elements. They include elements 57-71, or lanthanides, and 89-103, or actinides. The lanthanides are very similar, and t ...

                                               

Inorganic compound

An inorganic compound is a chemical compound that does not have carbon–hydrogen bonds that is, it is not an organic compound. That means it is not a carbon-based compound.

                                               

Iodine heptafluoride

Iodine heptafluoride is a chemical compound. Its chemical formula is IF 7. It contains iodine and fluoride ions. The iodine is in its 7 oxidation state.

                                               

Iodine trichloride

Iodine trichloride is a chemical compound. Its chemical formula is ICl 3. It has iodine and chloride ions in it. The iodine is in the 3 oxidation state.

                                               

Iridium

Iridium is the 77th element on the periodic table. Its symbol is Ir. Irs atomic number is 77. Iridium is a metal. Like other metals in the platinum group, Iridium is a rare and expensive "noble metal" and is a transition metal. It looks like plat ...

                                               

Iron oxide

Iron oxides are chemical compounds. There are sixteen known iron oxides. Iron oxides are used in pigments. It is used in both man-made and natural pigments. Venetian red haematite, Magnetite Fe 3 O 4, or a mixture of oxides make black or purple p ...

                                               

Iron sulfide

Iron sulfide is the chemical compound FeS, a black solid. It is made of iron and sulfide ions. FeS has iron in its 2 oxidation state. It reacts with acids such as hydrochloric acid to make hydrogen sulfide gas. In plural, "iron sulfides" may refe ...

                                               

Iron(III) oxide

Iron oxide, also known as rust, is a reddish substance, an iron oxide. It has a chemical formula of Fe 2 O 3. It is made by the reaction of iron with oxygen. It is found naturally in the ground as hematite, the major ore which blast furnaces use ...

                                               

Iron(III) sulfate

It is found as a mixed ironIII aluminium sulfate. This is the anhydrous form. Several hydrated forms are found, too. Much more ironIII sulfate is found in Mars. One of the rovers that travel on Mars got stuck in a pit of ironIII sulfate and could ...

                                               

Isodesmic reaction

An isodesmic reaction is a chemical reaction where the type of chemical bonds broken in the reactant are the same as the type of bonds formed in the reaction product. This type of reaction is often used as a hypothetical reaction in thermochemist ...

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Pino - logical board game which is based on tactics and strategy. In general this is a remix of chess, checkers and corners. The game develops imagination, concentration, teaches how to solve tasks, plan their own actions and of course to think logically. It does not matter how much pieces you have, the main thing is how they are placement!

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