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Ammonium Pertechnetate
Ammonium pertechnetate is a chemical compound with the formula NH4TcO4. It is the ammonium salt of pertechnetic acid. The most common form uses 99Tc. The compound is readily soluble in aqueous solutions forming ammonium and pertechnetate ions. It can be synthesized by the reaction of pertechnetic acid and ammonium nitrate Ammonium nitrate is a chemical compound with the chemical formula . It is a white crystalline salt consisting of ions of ammonium and nitrate. It is highly soluble in water and hygroscopic as a solid, although it does not form hydrates. It ...: :HTcO4 + NH4NO3 → NH4TcO4 + HNO3 It thermally decomposes under inert atmosphere at 700 °C to technetium dioxide: :NH4TcO4 → TcO2 + 2 H2O + 1/2 N2 References {{Technetium compounds Pertechnetates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Nitrate
Ammonium nitrate is a chemical compound with the chemical formula . It is a white crystalline salt consisting of ions of ammonium and nitrate. It is highly soluble in water and hygroscopic as a solid, although it does not form hydrates. It is predominantly used in agriculture as a high-nitrogen fertilizer.Karl-Heinz Zapp "Ammonium Compounds" in ''Ullmann's Encyclopedia of Industrial Chemistry'' 2012, Wiley-VCH, Weinheim. Global production was estimated at 21.6 million tonnes in 2017. Its other major use is as a component of explosive mixtures used in mining, quarrying, and civil construction. It is the major constituent of ANFO, a popular industrial explosive which accounts for 80% of explosives used in North America; similar formulations have been used in improvised explosive devices. Many countries are phasing out its use in consumer applications due to concerns over its potential for misuse. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Pertechnetate
Sodium pertechnetate is the inorganic compound with the formula NaTcO4. This colourless salt contains the pertechnetate anion, . The radioactive anion is an important radiopharmaceutical for diagnostic use. The advantages to include its short half-life of 6 hours and the low radiation exposure to the patient, which allow a patient to be injected with activities of more than 30 millicuries. is a precursor to a variety of derivatives that are used to image different parts of the body. Chemistry is the starting material for most of the chemistry of technetium. Pertechnetate salts are usually colorless. is produced by oxidizing technetium with nitric acid or with hydrogen peroxide. The pertechnetate anion is similar to the permanganate anion but is a weaker oxidizing agent. It is tetrahedral and diamagnetic. The standard electrode potential for / is only +0.738 V in acidic solution, as compared to +1.695 V for /. Because of its diminished oxidizing power, is stable in alkaline so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Pertechnetate
The pertechnetate ion () is an oxyanion with the chemical formula . It is often used as a convenient water-soluble source of isotopes of the radioactive element technetium (Tc). In particular it is used to carry the 99mTc isotope (half-life 6 hours) which is commonly used in nuclear medicine in several nuclear scanning procedures. A technetate(VII) salt is a compound containing this ion. Pertechnetate compounds are salts of technetic(VII) acid. Pertechnetate is analogous to permanganate but it has little oxidizing power. Pertechnetate has higher oxidation power than perrhenate. Understanding pertechnetate is important in understanding technetium contamination in the environment and in nuclear waste management. Chemistry is the starting material for most of the chemistry of technetium. Pertechnetate salts are usually colorless. is produced by oxidizing technetium with nitric acid or with hydrogen peroxide. The pertechnetate anion is similar to the permanganate anion but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Pertechnetate
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third most abundant metal, after iron and aluminium. The most common calcium compound on Earth is calcium carbonate, found in limestone and the fossilised remnants of early sea life; gypsum, anhydrite, fluorite, and apatite are also sources of calcium. The name derives from Latin ''calx'' " lime", which was obtained from heating limestone. Some calcium compounds were known to the ancients, though their chemistry was unknown until the seventeenth century. Pure calcium was isolated in 1808 via electrolysis of its oxide by Humphry Davy, who named the element. Calcium compounds are widely used in many industries: in foods an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perchloric Acid
Perchloric acid is a mineral acid with the formula H Cl O4. Usually found as an aqueous solution, this colorless compound is a stronger acid than sulfuric acid, nitric acid and hydrochloric acid. It is a powerful oxidizer when hot, but aqueous solutions up to approximately 70% by weight at room temperature are generally safe, only showing strong acid features and no oxidizing properties. Perchloric acid is useful for preparing perchlorate salts, especially ammonium perchlorate, an important rocket fuel component. Perchloric acid is dangerously corrosive and readily forms potentially explosive mixtures. History Perchloric acid was first synthesized (together with potassium perchlorate) by Austrian chemist and called "oxygenated chloric acid" in mid-1810s; French pharmacist Georges-Simon Serullas introduced the modern designation along with discovering its solid monohydrate (which he, however, mistook for an anhydride). Production Perchloric acid is produced industrially by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pertechnetic Acid
Pertechnetic acid (HTcO4) is a compound of technetium that is produced by reacting technetium(VII) oxide (Tc2O7) with water or strong oxidizing acids, such as nitric acid, concentrated sulfuric acid or aqua regia. The dark red hygroscopic substance is a strong acid, with a p''K''a of 0.32, as such it exists almost entirely as the pertechnetate ion in aqueous solution. The red color in solution is thought to be due to the formation of the polyoxometallate . Use of strong enough acid solution, for example, concentrated sulfuric acid, can generate the protonated form, which then exists as the octahedral TcO3(OH)(H2O)2 dihydrate In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ... complex. See also * Sodium pertechnetate References {{Technetium compounds Pertechnetates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Technetium
Technetium (43Tc) is one of the two elements with that have no stable isotopes; the other such element is promethium. – Elements marked with a * have no stable isotope: 43, 61, and 83 and up. It is primarily artificial, with only trace quantities existing in nature produced by spontaneous fission (there are an estimated grams of 99Tc per gram of pitchblende) or neutron capture by molybdenum. The first isotopes to be synthesized were 97Tc and 99Tc in 1936, the first artificial element to be produced. The most stable radioisotopes are 97Tc (half-life of 4.21 million years), 98Tc (half-life: 4.2 million years), and 99Tc (half-life: 211,100 years). Thirty-three other radioisotopes have been characterized with atomic masses ranging from 85Tc to 120Tc. Most of these have half-lives that are less than an hour; the exceptions are 93Tc (half-life: 2.75 hours), 94Tc (half-life: 4.883 hours), 95Tc (half-life: 20 hours), and 96Tc (half-life: 4.28 days). Technetium also has numerous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium
The ammonium cation is a positively-charged polyatomic ion with the chemical formula or . It is formed by the protonation of ammonia (). Ammonium is also a general name for positively charged or protonated substituted amines and quaternary ammonium cations (), where one or more hydrogen atoms are replaced by organic groups (indicated by R). Acid–base properties The ammonium ion is generated when ammonia, a weak base, reacts with Brønsted acids (proton donors): :H+ + NH3 -> H4 The ammonium ion is mildly acidic, reacting with Brønsted bases to return to the uncharged ammonia molecule: : H4 + B- -> HB + NH3 Thus, treatment of concentrated solutions of ammonium salts with strong base gives ammonia. When ammonia is dissolved in water, a tiny amount of it converts to ammonium ions: :H2O + NH3 OH- + H4 The degree to which ammonia forms the ammonium ion depends on the pH of the solution. If the pH is low, the equilibrium shifts to the right: more ammonia molecules are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pertechnetate
The pertechnetate ion () is an oxyanion with the chemical formula . It is often used as a convenient water-soluble source of isotopes of the radioactive element technetium (Tc). In particular it is used to carry the 99mTc isotope (half-life 6 hours) which is commonly used in nuclear medicine in several nuclear scanning procedures. A technetate(VII) salt is a compound containing this ion. Pertechnetate compounds are salts of technetic(VII) acid. Pertechnetate is analogous to permanganate but it has little oxidizing power. Pertechnetate has higher oxidation power than perrhenate. Understanding pertechnetate is important in understanding technetium contamination in the environment and in nuclear waste management. Chemistry is the starting material for most of the chemistry of technetium. Pertechnetate salts are usually colorless. is produced by oxidizing technetium with nitric acid or with hydrogen peroxide. The pertechnetate anion is similar to the permanganate anion but is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Nitrate
Ammonium nitrate is a chemical compound with the chemical formula . It is a white crystalline salt consisting of ions of ammonium and nitrate. It is highly soluble in water and hygroscopic as a solid, although it does not form hydrates. It is predominantly used in agriculture as a high-nitrogen fertilizer.Karl-Heinz Zapp "Ammonium Compounds" in ''Ullmann's Encyclopedia of Industrial Chemistry'' 2012, Wiley-VCH, Weinheim. Global production was estimated at 21.6 million tonnes in 2017. Its other major use is as a component of explosive mixtures used in mining, quarrying, and civil construction. It is the major constituent of ANFO, a popular industrial explosive which accounts for 80% of explosives used in North America; similar formulations have been used in improvised explosive devices. Many countries are phasing out its use in consumer applications due to concerns over its potential for misuse. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technetium Dioxide
Technetium(IV) oxide, also known as technetium dioxide, is a chemical compound with the formula TcO2 which forms the dihydrate, TcO2·2H2O, which is also known as technetium(IV) hydroxide. It is a radioactive black solid which slowly oxidizes in air. Preparation Technetium dioxide was first produced in 1949 by electrolyzing a solution of ammonium pertechnetate under ammonium hydroxide and this method is used for separating technetium from molybdenum and rhenium. There are now more efficient ways of producing the compound, such as the reduction of ammonium pertechnetate by zinc metal and hydrochloric acid, stannous chloride, hydrazine, hydroxylamine, ascorbic acid, by the hydrolysis of potassium hexachlorotechnate or by the decomposition of ammonium pertechnetate at 700 °C under an inert atmosphere: :2 NH4TcO4 → 2 TcO2 + 4 H2O + N2 All of these methods except the last lead to the formation of the dihydrate. The most modern method of producing this compound is by the reaction of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
