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Nickel(II) Chromate
Nickel(II) chromate (NiCrO4) is an acid-soluble compound, red-brown in color, with high tolerances for heat. It and the ions that compose it have been linked to tumor formation and gene mutation, particularly to wildlife. Synthesis Nickel(II) chromate can be formed in the lab by heating a mixture of chromium(III) oxide and nickel oxide at between 700 °C and 800 °C under oxygen at 1000 atm pressure. It can be produced at 535 °C and 7.3 bar oxygen, but the reaction takes days to complete. If the pressure is too low or temperature too high but above 660 °C, then the nickel chromium spinel NiCr2O4 forms instead. Karin Brandt also claimed to make nickel chromate using a hydrothermal technique. Precipitates of Ni2+ ions with chromate produce a brown substance that contains water. Properties The structure of nickel chromate is the same as for chromium vanadate, CrVO4. Crystals have an orthorhombic structure with unit cell sizes a = 5.482 Å, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrochloric Acid
Hydrochloric acid, also known as muriatic acid, is an aqueous solution of hydrogen chloride. It is a colorless solution with a distinctive pungent smell. It is classified as a strong acid Acid strength is the tendency of an acid, symbolised by the chemical formula HA, to dissociate into a proton, H+, and an anion, A-. The dissociation of a strong acid in solution is effectively complete, except in its most concentrated solutions .... It is a component of the gastric acid in the digestive systems of most animal species, including humans. Hydrochloric acid is an important laboratory reagent and industrial chemical. History In the early tenth century, the Persian physician and alchemist Abu Bakr al-Razi ( 865–925, Latin: Rhazes) conducted experiments with sal ammoniac (ammonium chloride) and vitriol (hydrated sulfates of various metals), which he distilled together, thus producing the gas hydrogen chloride. In doing so, al-Razi may have stumbled upon a primitive method ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium Chromate
Magnesium chromate is a chemical compound, with the formula MgCrO4. It is a yellow, odorless, water-soluble solid with several important industrial uses. This chromate can be manufactured as a powder. History Before 1940, the literature about magnesium chromate and its hydrates was sparse, but studies starting in that year looked at its properties and solubility. Uses It is available commercially in a variety of powders, from nanoscale to micron-sized, either as an anhydrous or hydrated form. As a hydrate, it is useful as a corrosion inhibitor and pigment, or as an ingredient in cosmetics. In 2011, an undecahydrate (containing 11 molecules of water) of this compound was discovered by scientists at the University College London. Hazards Magnesium chromate hydrate should be stored at room temperature, and there is no current therapeutic use. It is a confirmed carcinogen A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cadmium Chromate
Cadmium chromate is the inorganic compound with the formula CdCrO4. It is relevant to chromate conversion coating Chromate conversion coating or alodine coating is a type of conversion coating used to passivate steel, aluminium, zinc, cadmium, copper, silver, titanium, magnesium, and tin alloys. The coating serves as a corrosion inhibitor, as a primer t ..., which is used to passivate common metal alloys such as aluminium, zinc, cadmium, copper, silver, magnesium, and tin. In conversion coating chromate reacts with these metals to prevent corrosion, retain electrical conductivity, and provide a finish for the appearance of the final alloy products. This process is commonly used on hardware and tool items. Chromate species take on their distinctive yellow color when coated. References {{Chromates and dichromates Cadmium compounds Chromates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel(II) Molybdate
Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow to react with air under standard conditions because a passivation layer of nickel oxide forms on the surface that prevents further corrosion. Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere. Meteoric nickel is found in combination with iron, a reflection of the origin of those elements as major end products of supernova nucleosynthesis. An iron–nickel mixture is thought to compose Earth's outer and inner cores. Use of nickel (as natural meteoric nickel–iron alloy) has been traced as far back as 3500 BCE. Nickel was first isolated and classified a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel(II) Tungstate
Nickel tungstate is an inorganic compound of nickel, tungsten and oxygen, with the chemical formula of NiWO4. Preparation Nickel tungstate can be prepared by the reaction of nickel(II) nitrate and sodium tungstate:A. Kuzmin, J. Purans, R. Kalendarev: Local structure and vibrational dynamics in NiWO4.' In: ''Ferroelectrics.'' 258, 2001, S. 21, . :Ni(NO3)2 + Na2WO4 → NiWO4 + 2 NaNO3 Nickel tungstate can also be prepared by the reaction of nickel(II) oxide and tungsten(VI) oxide. It can also be obtained by the reaction of ammonium metatungstate and nickel(II) nitrateJ.M. Quintana-Melgoza, J. Cruz-Reyes, M. Avalos-Borja: ''Synthesis and characterization of NiWO4 crystals.'' In: ''Materials Letters.'' 47, 2001, S. 314, . or from the reaction of sodium tungstate, nickel(II) chloride and sodium chloride.R. O. Keeling: ''The structure of NiWO4.'' In: ''Acta Crystallographica.'' 10, S. 209, . Nickel tungstate undergoes a phase transition at 700°C. Properties ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
