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Ferrous
In chemistry, the adjective Ferrous indicates a compound that contains iron(II), meaning iron in its +2 oxidation state, possibly as the divalent cation Fe2+. It is opposed to " ferric" or iron(III), meaning iron in its +3 oxidation state, such as the trivalent cation Fe3+.ferrous entry in the online dictionary. Accessed on 2008-04-19. This usage has been largely replaced by the nomenclature, which calls for the oxidation state being indicated by Roman numerals in parentheses, such as |
Non-ferrous
In metallurgy, non-ferrous metals are metals or alloys that do not contain iron (allotropes of iron, ferrite, and so on) in appreciable amounts. Generally more costly than ferrous metals, non-ferrous metals are used because of desirable properties such as low weight (e.g. aluminium), higher conductivity (e.g. copper), non-magnetic properties or resistance to corrosion (e.g. zinc). Some non-ferrous materials are also used in the iron and steel industries. For example, bauxite is used as flux for blast furnaces, while others such as wolframite, pyrolusite, and chromite are used in making ferrous alloys. Important non-ferrous metals include aluminium, copper, lead, tin, titanium, and zinc, and alloys such as brass. Precious metals such as gold, silver, and platinum and exotic or rare metals such as mercury, tungsten, beryllium, bismuth, cerium, cadmium, niobium, indium, gallium, germanium, lithium, selenium, tantalum, tellurium, vanadium, and zirconium are also non-ferrous. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen (32.1% and 30.1%, respectively), forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching or higher, about higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BCE and the use of iron tools and weapons began to displace copper alloys, in some regions, only around 1200 BCE. That event is considered the transition from the Bronze Age to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron(II) Sulfate
Iron(II) sulfate (British English: iron(II) sulphate) or ferrous sulfate denotes a range of salts with the formula Fe SO4·''x''H2O. These compounds exist most commonly as the heptahydrate (''x'' = 7) but several values for x are known. The hydrated form is used medically to treat iron deficiency, and also for industrial applications. Known since ancient times as copperas and as green vitriol (vitriol is an archaic name for sulfate), the blue-green heptahydrate (hydrate with 7 molecules of water) is the most common form of this material. All the iron(II) sulfates dissolve in water to give the same aquo complex e(H2O)6sup>2+, which has octahedral molecular geometry and is paramagnetic. The name copperas dates from times when the copper(II) sulfate was known as blue copperas, and perhaps in analogy, iron(II) and zinc sulfate were known respectively as green and white copperas. It is on the World Health Organization's List of Essential Medicines. In 2020, it was the 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metal
A metal (from ancient Greek, Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. Metals are typically ductile (can be drawn into wires) and malleable (they can be hammered into thin sheets). These properties are the result of the ''metallic bond'' between the atoms or molecules of the metal. A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polythiazyl, polymeric sulfur nitride. In physics, a metal is generally regarded as any substance capable of conducting electricity at a temperature of absolute zero. Many elements and compounds that are not normally classified as metals become metallic under high pressures. For example, the nonmetal iodine gradually becomes a metal at a pressure of between 40 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron(II) Chloride
Iron(II) chloride, also known as ferrous chloride, is the chemical compound of formula FeCl2. It is a paramagnetic solid with a high melting point. The compound is white, but typical samples are often off-white. FeCl2 crystallizes from water as the greenish tetrahydrate, which is the form that is most commonly encountered in commerce and the laboratory. There is also a dihydrate. The compound is highly soluble in water, giving pale green solutions. Production Hydrated forms of ferrous chloride are generated by treatment of wastes from steel production with hydrochloric acid. Such solutions are designated "spent acid," or "pickle liquor" especially when the hydrochloric acid is not completely consumed: :Fe + 2 HCl → FeCl2 + H2 The spent acid requires treatment if it is disposed. Ferrous chloride is used in the manufacturing of ferric chloride. Ferrous chloride can also be used to regenerate hydrochloric acid. It is also a byproduct from titanium production, since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron(II,III) Oxide
Iron(II,III) oxide is the chemical compound with formula Fe3O4. It occurs in nature as the mineral magnetite. It is one of a number of iron oxides, the others being iron(II) oxide (FeO), which is rare, and iron(III) oxide (Fe2O3) which also occurs naturally as the mineral hematite. It contains both Fe2+ and Fe3+ ions and is sometimes formulated as FeO ∙ Fe2O3. This iron oxide is encountered in the laboratory as a black powder. It exhibits permanent magnetism and is ferrimagnetic, but is sometimes incorrectly described as ferromagnetic. Its most extensive use is as a black pigment. For this purpose, it is synthesized rather than being extracted from the naturally occurring mineral as the particle size and shape can be varied by the method of production. Preparation Heated iron metal interacts with steam to form iron oxide and hydrogen gas. 3Fe + 4H2O->Fe3O4 + 4H2 Under anaerobic conditions, ferrous hydroxide (Fe(OH)2) can be oxidized by water to form magnetite a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron(II)
In chemistry, iron(II) refers to the element iron in its +2 oxidation state. In ionic compounds (salts), such an atom may occur as a separate cation (positive ion) denoted by Fe2+. The adjective ferrous or the prefix ferro- is often used to specify such compounds — as in "ferrous chloride" for iron(II) chloride, . The adjective "ferric" is used instead for iron(III) salts, containing the cation or Fe3+. The word ferrous is derived from the Latin word ''ferrum'' for iron. Iron(II) atoms may also occur as coordination complexes, such as the polymer iron(II) oxalate dihydrate, or ; and organometallic compounds, such as the neutral molecule ferrocene, or . Iron is almost always encountered in the oxidation states 0 (as in the metal), +2, or +3. Solid iron(II) salts are relatively stable in air, but in the presence of air and water they tend to oxidize to iron(III) salts that include hydroxide () or oxide () anions. Iron(II) and life All known forms of life require ir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation State
In chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to different atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. Conceptually, the oxidation state may be positive, negative or zero. While fully ionic bonds are not found in nature, many bonds exhibit strong ionicity, making oxidation state a useful predictor of charge. The oxidation state of an atom does not represent the "real" formal charge on that atom, or any other actual atomic property. This is particularly true of high oxidation states, where the ionization energy required to produce a multiply positive ion is far greater than the energies available in chemical reactions. Additionally, the oxidation states of atoms in a given compound may vary depending on the choice of electronegativity scale used in their calculation. Thus, the oxidation state of an atom in a compound is purely a formalism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rust
Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (FeO(OH), Fe(OH)3), and is typically associated with the corrosion of refined iron. Given sufficient time, any iron mass, in the presence of water and oxygen, could eventually convert entirely to rust. Surface rust is commonly flaky and friable, and provides no passivational protection to the underlying iron, unlike the formation of patina on copper surfaces. ''Rusting'' is the common term for corrosion of elemental iron and its alloys such as steel. Many other metals undergo similar corrosion, but the resulting oxides are not commonly called "rust". Several forms of rust are distinguishable both visually and by spectroscopy, and form under different circumstances. Other forms of rust include the result of reactions between iron and chlo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cation
An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention. The net charge of an ion is not zero because its total number of electrons is unequal to its total number of protons. A cation is a positively charged ion with fewer electrons than protons while an anion is a negatively charged ion with more electrons than protons. Opposite electric charges are pulled towards one another by electrostatic force, so cations and anions attract each other and readily form ionic compounds. Ions consisting of only a single atom are termed atomic or monatomic ions, while two or more atoms form molecular ions or polyatomic ions. In the case of physical ionization in a fluid (gas or liquid), "ion pairs" are created by spontaneous molecule collisions, where each generated pair consists of a free electron an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valence (chemistry)
In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an atom of a given element is determined by the number of hydrogen atoms that it combines with. In methane, carbon has a valence of 4; in ammonia, nitrogen has a valence of 3; in water, oxygen has a valence of 2; and in hydrogen chloride, chlorine has a valence of 1. Chlorine, as it has a valence of one, can be substituted for hydrogen. Phosphorus has a valence of 5 in phosphorus pentachloride, . Valence diagrams of a compound represent the connectivity of the elements, with lines drawn between two elements, sometimes called bonds, representing a saturated valency for each element. The two tables below show some examples of different compounds, their valence diagrams, and the valences for each element of the compound. Modern definitions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pourbaix Diagram Of Iron
In electrochemistry, and more generally in solution chemistry, a Pourbaix diagram, also known as a potential/pH diagram, EH–pH diagram or a pE/pH diagram, is a plot of possible thermodynamically stable phases (''i.e.'', at chemical equilibrium) of an aqueous electrochemical system. Boundaries (50 %/50 %) between the predominant chemical species (aqueous ions in solution, or solid phases) are represented by lines. As such a Pourbaix diagram can be read much like a standard phase diagram with a different set of axes. Similarly to phase diagrams, they do not allow for reaction rate or kinetic effects. Beside potential and pH, the equilibrium concentrations are also dependent upon, e.g., temperature, pressure, and concentration. Pourbaix diagrams are commonly given at room temperature, atmospheric pressure, and molar concentrations of 10−6 and changing any of these parameters will yield a different diagram. The diagrams are named after Marcel Pourbaix (1904–1998), the Russian-bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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