![]() These claims are not supported by scientific evidence. Only mercury (38.9 ☌, or 38.02 ☏) has a lower melting point than caesium, and the low melting points of alkali metals are due to their vast interatomic distances and weak. DNA fragments with differing A-T or G-C content).Ĭaesium chloride (non-radioactive) is also promoted as an alternative cancer therapy. The alkali metals have the lowest melting points of any nongaseous group in the periodic table, ranging from 179☌ (354☏) for lithium to 28.5☌ (83.3☏) for caesium. This allows separation of DNA of different densities (e.g. At this point, the DNA will stop migrating. When DNA is centrifuged in this solution, fragments of DNA will migrate down the tube until they reach a zone where the density of the DNA is equal to the density of the solution. In this method, a caesium chloride solution is centrifuged, allowing centrifugal and diffusive forces to establish a concentration gradient (and thus a density gradient) within the centrifuge tube. See the Goiânia accident for further details.Ĭaesium chloride is also widely used in the centrifugation of DNA, in a technique known as isopycnic centrifugation. In Brazil, such a source was stolen by scrap metal workers from a disused radiotherapy clinic, and serious injuries and deaths occurred as a result of external gamma exposure and internal exposure (the source was smashed open, releasing the water soluble caesium chloride). Sodium Na Atomic Number: 11 Atomic Weight: 22.990 Melting Point: 370.87 Boiling Point: 1156 Electronegativity: 0. It is normal to use a thimble-shaped can of radioactive caesium chloride to provide the active source in a teletherapy type radiotherapy unit. Caesium 55 xenon caesium barium RbCsFr Periodic Table - Extended Periodic Table General Name, Symbol, Number caesium, Cs, 55 Chemical series alkali. ![]() As a result it is not possible with any of the insoluble caesium compounds to create the source. But for teletherapy sources, the radioactive density (Ci in a given volume) needs to be very high. For instance, radiothermal generators (RTGs) often use strontium titanate because it is insoluble in water. In the production of radioactive sources it is normal to choose a chemical form of the radioisotope which will not be dispersed with ease in the environment as a result of an accident where the source is smashed open. ![]() Radioisotopes of caesium chloride are used in nuclear medicine, including treatment of cancer. If the two atom types are similar in size (imagine field hockey balls packed with tennis balls) then in the cubic lattice the structure will be like that of sodium chloride.Ĭaesium chloride is used in the preparation of electrically conducting glasses. It is the case that in a cubic 1:1 solid where one atom type is much larger than the other that the caesium chloride type lattice is obtained, it can be thought of as a combination of basketballs and golf balls packed in a cubic manner with the golf balls in the gaps between the basketballs. The caesium chloride structure is composed of interlocking simple cubic lattices of anions and cations. ![]()
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