Then, in , Sir Humphry Davy used electrolysis to isolate the element barium, which barite is composed of. The interesting nature of the element, its uses, and its properties then began attracting the attention of current scientists. When the mineral barite is heated with carbon, it reduces to barium sulfide. This barium sulfide is then treated upon to form other compounds of barium e. Barium nitrate is a strong oxidizing agent, similar to other nitrates. Barium sulfate is highly insoluble, and barium ions can be used to detect small amounts of sulfate ions.
Barium salts can be combined with concentrated sulfuric acid to form barium sulfate along with the respective acid of the salt. This technique is commonly used in amateur labs to produce acids like perchloric acid or nitric acid. Barium compounds are used to give a green color to fireworks and other pyrotechnics. Soluble compounds of barium, along with barium carbonate and barium fluoride, are toxic and must be handled with care.
Barium carbonate is used in some parts of the world as a rodenticide. However, because it resembled flour, it has been the cause of many poisonings and deaths. Barium, when exposed to oxygen at room temperature, quickly oxidizes and produces BaO and BaO 2. It is usually stored under mineral oil. The element barium reacts with acids, alcohol, and water. In fact, it vigorously reacts with water to form barium hydroxide.
However, the reaction is not as violent as it is with the alkali metals. Commercially, barium is produced when the electrolysis of molten barium chloride BaCl 2 occurs. Barium oxide BaO reacting with aluminum or silicon at high temperatures also produces pure barium. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment. The percentage of the world reserves located in the country with the largest reserves.
A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Specific heat capacity is the amount of energy needed to change the temperature of a kilogram of a substance by 1 K.
A measure of the stiffness of a substance. It provides a measure of how difficult it is to extend a material, with a value given by the ratio of tensile strength to tensile strain. A measure of how difficult it is to deform a material. It is given by the ratio of the shear stress to the shear strain. A measure of how difficult it is to compress a substance. It is given by the ratio of the pressure on a body to the fractional decrease in volume.
A measure of the propensity of a substance to evaporate. It is defined as the equilibrium pressure exerted by the gas produced above a substance in a closed system. This Site has been carefully prepared for your visit, and we ask you to honour and agree to the following terms and conditions when using this Site. Copyright of and ownership in the Images reside with Murray Robertson. The RSC has been granted the sole and exclusive right and licence to produce, publish and further license the Images.
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Periodic Table. Glossary Allotropes Some elements exist in several different structural forms, called allotropes. Discovery date Discovered by Humphry Davy Origin of the name The name comes from the Greek 'barys', meaning heavy. Glossary Group A vertical column in the periodic table. Fact box. Glossary Image explanation Murray Robertson is the artist behind the images which make up Visual Elements.
Appearance The description of the element in its natural form. Biological role The role of the element in humans, animals and plants. Natural abundance Where the element is most commonly found in nature, and how it is sourced commercially. Uses and properties. Image explanation. Barium is a soft, silvery metal that rapidly tarnishes in air and reacts with water. Barium is not an extensively used element. Most is used in drilling fluids for oil and gas wells. It is also used in paint and in glassmaking.
All barium compounds are toxic; however, barium sulfate is insoluble and so can be safely swallowed. A suspension of barium sulfate is sometimes given to patients suffering from digestive disorders. Barium is a heavy element and scatters X-rays, so as it passes through the body the stomach and intestines can be distinguished on an X-ray. Barium carbonate has been used in the past as a rat poison.
Barium nitrate gives fireworks a green colour. Biological role. Barium has no known biological role, although barium sulfate has been found in one particular type of algae. Barium is toxic, as are its water- or acid-soluble compounds. Natural abundance. Barium occurs only in combination with other elements. The major ores are barite barium sulfate and witherite barium carbonate. Barium metal can be prepared by electrolysis of molten barium chloride, or by heating barium oxide with aluminium powder.
Help text not available for this section currently. Elements and Periodic Table History. In the early s, Vincenzo Casciarolo, of Bologna, Italy, found some unusual pebbles. If they were heated to redness during the day, they would shine during the night. This was the mineral barite barium sulfate, BaSO 4.
When Bologna stone, as it became known, was investigated by Carl Scheele in s he realised it was the sulfate of an unknown element. Meanwhile a mineralogist, Dr William Withering, had found another curiously heavy mineral in a lead mine in Cumberland which clearly was not a lead ore. He named it witherite; it was later shown to be barium carbonate, BaCO 3.
Neither the sulfate nor the carbonate yielded up the metal itself using the conventional process of smelting with carbon. However, Humphry Davy at the Royal Institution in London produced it by the electrolysis of barium hydroxide in Atomic data.
Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom. Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk.
Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves.
Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators.
Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators.
Supply risk. Relative supply risk 8. Young's modulus A measure of the stiffness of a substance. Magnesium fires are very difficult to put out, since even in the absence of air, burning magnesium reacts with nitrogen to form magnesium nitride Mg 3 N 2 , and with water to produce magnesium hydroxide and hydrogen gas.
Magnesium is found in a number of familiar compounds. Magnesium hydroxide, Mg OH 2 , also known as milk of magnesia, is a laxative and antacid.
The "milk" in "milk of magnesia" refers to the fact that since magnesium hydroxide is not very soluble in water, it tends to form a chalky, white suspension that looks like milk — but with considerably different physiological effects. Green plants contain a molecule called chlorophyll , which consists of a flat ring of carbon and nitrogen atoms with a large open space in the middle, in which a magnesium ion is bound, held in place by the nitrogen atoms.
The chlorophyll molecule absorbs light from the sun, and in the process of photosynthesis, the energy from the light is converted into chemical energy that the plant can use to power a multitude of processes.
In organic chemistry, magnesium reacts with bromoalkanes hydrocarbons containing carbon-bromine bonds to form organomagnesium compounds known as Grignard reagents after their discoverer, Victor Grignard, who won a Nobel Prize in Chemistry, These compounds are extremely useful in forming new carbon-carbon bonds, and are often used in the synthesis of organic compounds.
Grignard reagents are notoriously sensitive to water, and care must be taken to ensure that the apparatus in which the reaction is being carried out is extremely dry. Calcium is a silver-colored, relatively soft metal.
The name of the element is derived from the Latin word for lime, calx. It is found in the Earth's crust at a concentration of 4.
Since calcium forms such hard minerals, it is useful in building materials, such as plaster, mortar, and cement. Mortar is made from calcium oxide, CaO, also known as lime, or quicklime.
When calcium oxide is treated with water it forms calcium hydroxide, Ca OH 2 , or slaked lime, which absorbs carbon dioxide from the air and gradually forms calcium carbonate, CaCO 3.
Lime, heated by hydrogen burning in oxygen, burns with a brilliant white light, which can be focused into a narrow beam visible over great distances. This kind of lighting was used in lighthouses, in surveying, and in theaters to produce spotlights leaving the actor "in the limelight".
Calcium chloride is a deliquescent it absorbs enough water from the air that it dissolves in the solution , and is used to remove moisture from the air in damp basements. It would take a stronger person that me to resist calling a freshly opened box of calcium chloride that wasn't behaving properly as a "juvenile deliquescent.
Strontium is a shiny, relatively soft metal. The name of the element is derived from Strontian, a town in Scotland where the mineral strontianite was discovered, from which strontium was first isolated.
It is found in the Earth's crust at a concentration of ppm, making it the 16th most abundant element. Strontium salts produce brilliant red colors when heated, and are used in fireworks and flares for this reason.
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