![]() ![]() It dissolves readily in dilute sulfuric acid to form solutions that contain yellow Dy (III) ions. It decomposes to form DyO(OH) at elevated temperatures but decomposes again to form Dy (III) oxide. The pure metal is quite electropositive and hazardous element for the environment because it reacts with water to form flammable hydrogen gas. It is relatively stable in air at room temperature but in a humid atmosphere, it forms a Dy (III) oxide layer. It is lanthanide that lies between terbium and holmium. The rare earth metal dysprosium is placed with the f-block elements of the periodic table. Like other lanthanides, it commonly uses three electrons for chemical bonding purposes to show a +3 oxidation number or state. The valence shell electron configuration of the metal is 4f 10 6s 2. The 66 electrons of dysprosium are distributed in different orbitals to give the following electronic configuration, The Greek word dysprositos means hard to get The metal is soft enough to cut by a knife and readily attacked and dissolved by dilute and concentrated mineral acids like sulfuric acid, nitric acid, or hydrochloric acid. It is oxidized in air to form an oxide layer. Propertiesĭysprosium is a silvery white soft solid at room temperature. In medicinal chemistry, the isotope 165Dy is used in arthritis therapy or radiosynovectomy. The primary radioactive decay mode of dysprosium isotopes is electron capture or alpha decay or beta decay. The most stable radioactive isotope is 154Dy (half-life 3×10 6 years) while the least stable radioactive isotope is 138Dy (half-life 200 ms). The atomic masses of these radioactive isotopes range from 138 to 173. ![]() It also contains 29 radioactive isotopes that can be synthesized by various artificial nuclear reactions. Naturally occurring dysprosium has seven isotopes with atomic mass ranging from 156 to 164. Today, it is primarily synthesized through an ion exchange process from monazite sand. It can be extracted or separated from rare earth minerals by ion exchange chromatography and solvent extraction process. It may also be found in smaller quantities in xenotime and fergusonite. Like other various lanthanides, dysprosium is found in the minerals monazite and bastnaesite. It is never found in nature as a free element and no dysprosium-dominant mineral has been found yet in the earth’s crust. The name of the rare earth metal was given for the Greek word dysprositos means hard to get. The pure form of the element was not isolated before the discovery of ion-exchange chromatography techniques. The metal and its compounds are used mainly for improving the workability of neodymium– iron– boron magnets, neutron-absorbing materials for control rods in nuclear power reactors, laser materials, and commercial lighting.ĭysprosium was first identified in 1886 by French chemist Paul Émile Lecoq de Boisbaudran. This fact has key implications for the building up of the periodic table of elements.The application of a pure form of dysprosium is very little. The ordering of the electrons in the ground state of multielectron atoms, starts with the lowest energy state (ground state) and moves progressively from there up the energy scale until each of the atom’s electrons has been assigned a unique set of quantum numbers. It is the Pauli exclusion principle that requires the electrons in an atom to occupy different energy levels instead of them all condensing in the ground state. In the periodic table, the elements are listed in order of increasing atomic number Z. The number of electrons in each element’s electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior. The configuration of these electrons follows from the principles of quantum mechanics. The chemical properties of the atom are determined by the number of protons, in fact, by number and arrangement of electrons. See also: Atomic Number – Does it conserve in a nuclear reaction? Atomic Number and Chemical PropertiesĮvery solid, liquid, gas, and plasma is composed of neutral or ionized atoms. It is the electrons that are responsible for the chemical bavavior of atoms, and which identify the various chemical elements. In a neutral atom there are as many electrons as protons moving about nucleus. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10 -19 coulombs. Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z. The nucleus is composed of protons and neutrons. The atom consist of a small but massive nucleus surrounded by a cloud of rapidly moving electrons. ![]()
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