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                      • ▸▸
                        • 🇬🇧 Europium
                        • 🇨🇳 銪
                        • 🇳🇱 Europium
                        • 🇫🇷 Europium
                        • 🇩🇪 Europium
                        • 🇮🇱 אירופיום
                        • 🇮🇹 Europio
                        • 🇯🇵 ユウロピウム
                        • 🇵🇹 Európio
                        • 🇷🇺 Европий
                        • 🇪🇸 Europio
                        • 🇸🇪 Europium

                        Europium: the essentials

                        Europium atoms have 63 electrons and the shell structure is 2.8.18.25.8.2. The ground state electronic configuration of neutral europium is [Xe].4f7.6s2 and the term symbol of europium is 8S7/2.

                        Europium: description  

                        网络斗地主下载Europium ignites in air at about 150 to 180°C. Europium is about as hard as lead and is quite ductile. It is the most reactive of the rare earth metals, quickly oxidising in air. It resembles calcium in its reaction with water. It is used in television screens to produce a red colour.

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

                        Europium: physical properties

                        More physical properties...

                        Europium: heat properties

                        More thermochemical properties...

                        Europium: atom sizes

                        More atomc size properties...

                        Europium: electronegativities

                        More electronegativity properties...

                        Europium: orbital properties

                        More orbital properties...

                        Europium: abundances

                        More geological data...

                        Europium: crystal structure

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

                        More crystallographic data...

                        Europium: biological data

                        Europium has no biological role.

                        More biological data...

                        Europium: uses

                        Uses...

                        Europium: reactions

                        网络斗地主下载 Reactions of europium as the element with air, water, halogens, acids, and bases where known.

                        View reactions of europium...

                        Europium: binary compounds

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

                        View binary compounds...

                        Europium: compound properties

                        Bond strengths; lattice energies of europium halides, hydrides, oxides (where known); and reduction potentials where known.

                        View compound properties...

                        Europium: history

                        Europium was discovered by Eugene Demarcay in 1901 at France. Origin of name: named after "Europe".

                        More history...

                        Europium: isotopes

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

                        Europium has two stable isotopes and both are used for the production of radioisotopes. Eu-151 is used for the production of Eu-152 which is used as a reference source in gammaspectroscopy. Eu-153 can be used for the production of high specific activity Sm-153 via fast neutron irradiation.

                        More isotope and NMR data...

                        Europium: isolation

                        Isolation: europium 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). Modern purification techniques for these lanthanoid salt mixtures are ingenious and involve selective complexation techniques, solvent extractions, and ion exchange chromatography.

                        Pure europium is available through the electrolysis of a mixture of molten EuCl3 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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