Chemical Property of Technetium
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Chemical Property:
- Melting Point:2250 ±50°
- Boiling Point:4265°C (estimate)
- PSA：0.00000
- Density:11.000
- LogP:-0.00250
- Hydrogen Bond Donor Count:0
- Hydrogen Bond Acceptor Count:0
- Rotatable Bond Count:0
- Exact Mass:96.90636
- Heavy Atom Count:1
- Complexity:0
- Purity/Quality:
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99%, *data from raw suppliers
TECHNETIUM 95.00% *data from reagent suppliers
Safty Information:
- Pictogram(s):
- Hazard Codes:
- MSDS Files:
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SDS file from LookChem
Useful:
- Chemical Classes:Physical/Radiation -> Radionuclides
- Canonical SMILES:[Tc]
- Recent ClinicalTrials:RAGE Inhibition to Decrease Therapy Cardiotoxicity in Women With Early Breast Cancer
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Description
Element with atomic number 43, group VIIB of the periodic table, aw 98.9062, valences of 4, 5, 6, 7; three radioactive isotopes of half-life more than 105 years, also several of relatively short half-life, some of which are β emitters. Technetium was first obtained by the deuteron bombardment of molybdenum, but since has been found in the fission products of uranium and plutonium. The chemistry of technetium has been studied by tracer techniques and is similar to that of rhenium and manganese. The free metal is obtained from reactor fission products by solvent extraction followed by crystallization as ammonium pertechnetate, which is reduced with hydrogen. The metal is silver-gray in appearance, mp 2200C (4000F), d 11.5, slightly magnetic. Compounds of the types TcO2, Tc2O7, NH4TcO4, etc. have been prepared. The pertechnetate ion has strong anticorrosive properties. Technetium and its alloys are superconductors and can be used to create high-strength magnetic fields at low temperature. Tc-99 (metastable) is the mostwidely used isotope in nuclear medicine.
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Uses
Metallurgical tracer, cryochemistry, corrosion
resistance, nuclear medicine. Minute quantities of TcO4- ion exert remarkable inhibition of the corrosion of soft iron in neutral aqueous solution: Cartledge, J. Am. Chem. Soc. 77, 2658 (1955). Technetium is one of the few artificially produced elements that has practical industrial applications.One is that a very small amount (55-ppm) added to iron creates a corrosion-resistantalloy metal. This property is shared with many of the other transition metallic elements, but notwith other artificially produced elements that have higher atomic numbers and are radioactive.A radioisotope of technetium is widely used in nuclear medicine. The patient is injectedwith saline solution containing Tc-99m (the superscript “m” means that the isotope is unstableand that its nuclei holds more energy than the regular Tc-99 nuclei into which it decays). Thismeans that the Tc-99m will start to emit energy and will finally decay and change to the regularnuclei of Tc-99 when injected into the patient. This energy is in the form of very penetratinggamma rays (a strong type of X-rays). The radioactive solution of Tc-99m may be combinedwith other elements that are absorbed by certain organs of the human body being diagnosedor treated. For instance, adding tin to the solution targets the red blood cells, whereas phosphorusin the solution concentrates the radioactive solution in heat muscles. The gamma raysare strong enough to expose an X-ray film that depicts the internal image of the organ underexamination. This procedure is safe because Tc-99m has a half-life of only 6.015 hours, andthe Tc-99 has a half-life of over 200,000 years. However, the radioactivity will be harmless inless than a day because the body rapidly eliminates the residual radioactive solution.Technetium is also used as an alloy metal to produce super-strong magnets that are supercooledto near absolute zero to improve their efficiency. Powerful magnets are used in imagingequipment and possibly in future magnetic driven trains. Its radioactivity makes it useful as atracer in the production of metals and tracing flowing fluids in pipelines.
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Physical properties
As the central member of the triad of metals in group 7, technetium (period 5) has similarphysical and chemical properties as its partners manganese (period 4) above it and rhenium(period 6) below it. The sizes of their atomic radii do not vary greatly: Mn = 127, Tc = 136,and Re = 137. Neither does their level of electronegativity vary significantly: Mn = 1.5, Tc =1.9, and Re = 1.9. Technetium metal is grayish-silver and looks much like platinum. As with most transitionelements, technetium in pure form is a noncorrosive metal. It requires only 55 ppm of technetiumadded to iron to transform the iron into a noncorroding alloy. Because of technetium’sradioactivity, its use as an alloy metal for iron is limited so as to not expose humans to unnecessaryradiation. Technetium’s melting point is 2,172°C, its boiling point is 4,877°C, and its density is11.50 g/cm3 .
