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                        • ▸▸
                          • 🇬🇧 Cerium
                          • 🇨🇳 鈰
                          • 🇳🇱 Cerium
                          • 🇫🇷 Cérium
                          • 🇩🇪 Cer
                          • 🇮🇱 סריום
                          • 🇮🇹 Cerio
                          • 🇯🇵 セリウム
                          • 🇵🇹 Cério
                          • 🇷🇺 Церий
                          • 🇪🇸 Cerio
                          • 🇸🇪 Cerium

                          Cerium: the essentials

                          Cerium atoms have 58 electrons and the shell structure is 2.8.18.19.9.2. The ground state electronic configuration of neutral cerium is [Xe].4f1.5d1.6s2 and the term symbol of cerium is 1G4.

                          Cerium: description  

                          网络斗地主下载Metallic cerium is prepared by reduction techniques, such as by reducing cerous fluoride with calcium, or by electrolysis of molten cerous chloride or other cerous halides.

                          网络斗地主下载Cerium is an iron-grey lustrous metal. It is malleable, and oxidises very readily at room temperature, especially in moist air. Except for europium, cerium is the most reactive of the rare-earth metals. It slowly decomposes in cold water, and rapidly in hot water. Alkali solutions and dilute and concentrated acids attack the metal rapidly. The pure metal may ignite when scratched with a knife.

                          网络斗地主下载It is the most abundant of the rare earth metals and is found in minerals including allanite, monazite, cerite, and bastnaesite. There are large deposits found in India, Brazil and the USA.

                          cerium
                          This sample is from , an attractive and safely packaged collection of the 92 naturally occurring elements that is available for sale.

                          Cerium: physical properties

                          More physical properties...

                          Cerium: heat properties

                          More thermochemical properties...

                          Cerium: electronegativities

                          More electronegativity properties...

                          Cerium: orbital properties

                          More orbital properties...

                          Cerium: abundances

                          More geological data...

                          Cerium: crystal structure

                          Ce crystal structure
                          The solid state structure of cerium is: bcc (body-centred cubic).

                          More crystallographic data...

                          Cerium: biological data

                          Cerium has no biological role but is said to stimulate the metabolism. The British Pharmaceutical Codex from 1907 indicates that cerium nitrate ["cerii nitras", Ce(NO3)3] was used to treat dyspepsia, pyrosis, and vomiting (especially "vomiting of pregnancy") in doses of 0.05-0.3 g ("1 to 5 grains") and that cerium salts have pharmacological properties similar to those of bismuth. The oxalate ["cerii oxalas", Ce2(C2O4)3.9H2O] was also used for "chronic vomiting, especially the vomiting of pregnancy." The doses were 0.6 g, three times a day for several days if necessary.

                          More biological data...

                          Cerium: uses

                          Uses...

                          Cerium: reactions

                          Reactions of cerium as the element with air, water, halogens, acids, and bases where known.

                          View reactions of cerium...

                          Cerium: binary compounds

                          Binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and other compounds of cerium where known.

                          View binary compounds...

                          Cerium: compound properties

                          网络斗地主下载 Bond strengths; lattice energies of cerium halides, hydrides, oxides (where known); and reduction potentials where known.

                          View compound properties...

                          Cerium: history

                          Cerium was discovered by Wilhelm von Hisinger, Jöns Jacob Berzelius, Martin Klaproth in 1803 at Sweden, Germany. Origin of name: named after the asteroid Ceres which discovered in 1801, 2 years before the element.

                          More history...

                          Cerium: isotopes

                          Isotope abundances of cerium
                          Isotope abundances of cerium with the most intense signal set to 100%.

                          网络斗地主下载There do not appear to be many applications for Ce isotopes although Ce-140 is used for the production of the radioisotope Ce-141 which is used for medical research purposes.

                          More isotope and NMR data...

                          Cerium: isolation

                          Isolation: cerium metal is available commercially so it is not normally necessary to make it in the laboratory, which is just as well as it is difficult to isolate as the pure metal. This is largely because of the way it is found in nature. The lanthanoids are found in nature in a number of minerals. The most important are xenotime, monazite, and bastnaesite. The first two are orthophosphate minerals LnPO4 (Ln deonotes a mixture of all the lanthanoids except promethium which is vanishingly rare) and the third is a fluoride carbonate LnCO3网络斗地主下载F. Lanthanoids with even atomic numbers are more common. The most comon lanthanoids in these minerals are, in order, cerium, lanthanum, neodymium, and praseodymium. Monazite also contains thorium and ytrrium which makes handling difficult since thorium and its decomposition products are radioactive.

                          For many purposes it is not particularly necessary to separate the metals, but if separation into individual metals is required, the process is complex. Initially, the metals are extracted as salts from the ores by extraction with sulphuric acid (H2SO4), hydrochloric acid (HCl), and sodium hydroxide (NaOH). The ceric ion, Ce(IV) is more easily hydrolysed than the lanthanide (III) ions and therefore precipitates as a salt upon treatment with an oxidizing agent such as KMnO4.

                          Pure cerium is available through the electrolysis of a mixture of molten CeCl3 and NaCl (or CaCl2) in a graphite cell which acts as cathode using graphite as anode. The other product is chlorine gas.

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