Zinc - Production, Application, Price Factors - Metal Alloy Price Factors Zinc Pennies Zinc The elemental metal named zinc is listed on the Periodic Table as “Zn”, has atomic number 30 and melts at 420 degrees Celsius (788 degrees Fahrenheit). Zinc is the 24th most abundant element in the crust of the Earth. Its color is grey metallic and can be polished to a silver shine. In nature, zinc is not found as a pure deposit, but as a chemical compound. The most commonly exploited zinc ore is a sulfide named sphalerite, with a zinc concentration of around 61% percent. The largest deposits of zinc are found in North America, Australia and Asia. Currently identified zinc resources total about 1.9 billion tonnes, which are estimated to be depleted between 2027 and 2055 at the current rate of consumption. History Statuettes and other ornaments made of a zinc alloy and some ancient writings, such as Greek, Roman and Indian recordings, mention the use of zinc as early as the 5th century BC.

Brass, an alloy made of copper and zinc, was already used in the 14th century BC in Palestine, containing 23% zinc in some specific cases. The isolation of pure zinc was achieved, probably independently by several people, at the end of the 17th century to as late as the mid 18th century. The German chemist Andreas Marggraf normally gets credit for the discovery of pure zinc in 1746, even though others before him have claimed discovery. Marggraf is therefore credited more with carefully describing the process and its basic theory, than the actual discovery. The making of zinc involves a number of steps which are described below. Mining Around 70% of the world’s zinc comes from mining, the remaining 30% originates from recycling zinc. Around 95% of the zinc is mined from sulfidic ore deposits and these mines are spread throughout the world. China is the largest producer of zinc, with around 29% of the global zinc output in 2010. Zinc metal is mined by using conventional blasting, drilling and hauling techniques. Froth flotation is used to separate zinc from other minerals after grinding the ore.

The final concentration of zinc is about 50% using this method, the remainder being sulfur and iron. Froth Flotation By a process known as froth flotation, zinc can be produced. Froth flotation is also used in the reduction of copper and lead ores. The process starts with grinding the zinc ore to fine material and subsequently mixing it with water, pine oil and flotation chemicals. The flotation chemicals attach themselves to any zinc particles present when the mixture is agitated with injected air. Bubbles rise up with zinc particles adhered to it, which are scooped up by scrapers, thus collecting zinc-laden froth. To remove water and oils, the froth is filtered. The remainder is roasted at 1371 degrees Celsius (2500 degrees Fahrenheit) into solid blocks called sinter. All the material has been completely converted to zinc oxide. There are two methods for refining zinc, which are listed below. Pyrometallurgy In order to refine the zinc to a higher grade ore it is processed in a blast furnace fueled by electricity , coke or natural gas . As the furnace reaches temperatures of up to 1204 degrees Celsius (2200 degrees Fahrenheit) the zinc ore is melted.

This process also generates carbon dioxide, which will reattach to the zinc as it cools to, once again, form zinc oxide. To prevent, or at least reduce, this reattachment, molten lead is sprayed on the zinc while it is still hot. The lead, because of its higher melting temperature of 550 degrees Celsius (1022 degrees Fahrenheit), dissolves the zinc. This mostly lead and zinc mixture is then carried to another chamber, where it will be cooled to 440 degrees Celsius (824 degrees Fahrenheit). Around this temperature, the zinc, because it is lighter, separates from the lead and is drained from the top. Subsequently it is cast into ingots. The lead is returned to the blast furnace to use again. To reach an even higher grade zinc ore, the zinc is kept molten and undisturbed for hours. Iron and other contaminants will settle slowly to the bottom, thus allowing the almost pure zinc to be drained from the top. With pyrometallurgical processes a maximum purity of 98% can be achieved.

While this is high enough to use the zinc for galvanization, it cannot be used to die-cast alloys, which requires 99,995% purity. Hydrometallurgy The hydrometallurgical process, also known as electrolysis, is used a lot more than the pyrometallurgical process. It consists of four steps: leaching, purifying, electrolysis and casting. In the first step, the zinc oxide is leached in a strong sulfuric. The result is a liquid called a leach product, which contains the zinc. It also produces a solid called a leach residue, which contains left-over metals (usually lead and silver) and is sold as a by-product. The basic chemical process is described below: ZnO + SO3 –> ZnSO4 The second step is called purification, because it removes certain elements from the zinc sulfate solution which can interfere with the electrolysis process. copper, cobalt, cadmium and nickel are removed and sold as by-products for further refining. The zinc sulfate solution must be very pure for electro-winning to be efficient. Electrolysis is the third step, producing an almost 100% pure zinc deposit.

The zinc is extracted from the zinc sulfate solution by electrowinning. An electric current is passed through the solution, which causes the zinc to deposit on aluminium sheets. Every day or two, the process is halted and the zinc-coated sheets are removed. Subsequently, the zinc is stripped from the sheets. About 3,900 KWh of electric power is expended producing one metric ton of zinc in this way. The final step is to melt the high grade zinc and cast it into very high grade (99,995% purity) ingots, or directly alloy and cast it into ingots. Transportation Zinc is usually transported in very large quantities on commercial shipping freighters, with the part between port and destination done by train or truck. Zinc is used in a number of applications Galvanizing against Corrosion Zinc is commonly used to coat iron or steel to protect these metals against corrosion. As it is more reactive than iron or steel, zinc will attract almost all oxidation until corrosion completely erodes the coated sheet. What is left is a surface protection layer of oxide and carbonate. This protection even functions after minor scratches and dents and can survive for many years.

Galvanization is used on metal roofing, bridges, guard rails, lightposts, heat exchangers and most visible to the consumer: car bodies. Coating zinc on another metal is accomplished by electrolytic plating of the metal – much like chrome plating a metal – or dipping it into molten zinc. Intricate Machine Parts An alloy made of very high grade zinc and aluminium is used to create die-cast parts which require little machining before they are used in an assembly. By injecting the alloy under pressure into the cavity of a two-part steel die, it fills the entire void within the mold. After the metal cools and the die halves are taken apart, the resulting zinc-alloy part is very close to the desired shape. Die-casting is used, among others, to create parts for aircraft, medical instruments and car parts like emblems and doorhandles. Electrodes An unique application of zinc uses its ability to transfer its corrosion resistance properties by electrical contact. In this manner, zinc is used as a sacrificial electrode. An example application for this kind of electrode is when it is attached to aluminium marine engines.

Especially in salt water, the oxidation process of the metals on the ship forms a weak electrical current, which may lead to corrosion of the hull and engine parts. By having a zinc sacrificial electrode present, it sacrifices itself by corrosion, negating the electrical current and thus protecting the aluminium hull and/or engine. Similarly, zinc is used as a component to produce batteries. In a dry cell battery, the zinc is housed in a metal can and creates a chemical reaction that results in a voltage potential between two contacts. An electrical device can be connected to the battery and powered by the electricity produced, until the available chemical reactants are spent. Alloys One widely used alloy which contains a large amount of zinc is brass. Brass is an alloy of copper mixed with 3% to 45% zinc, depending on the type of brass. Brass is superior to copper in areas like ductability, strength and corrosion resistance. This makes it useful in water valves, musical instruments and communication equipment. Other used alloys that contain substantial amounts of zinc include aluminium solder, commercial bronze and nickel silver. It is also the primary metal used in producing one cent coins in the United States.

The zinc coin is coated with a layer of copper to give the false impression of a copper coin. Trading The trading of Zinc futures takes place mainly on the London Metal Exchange (LME). This exchange regulates and monitors (electronic) trading of various metal types. Price Factors Zinc futures prices are influenced by a number of factors. Global supply of zinc is a major price determining factor. In the case of over-production, prices will rapidly fall. Mining activities will consequently drop which will eventually cause a deficit in supply. This will again raise prices to a standard level and this cycle will repeat itself. Substitutes can also greatly influence the demand for zinc. Metals such as aluminum and magnesium are alternatives as die-cast materials and as such can influence price movements of zinc. In the event of rising prices of aluminum and magnesium the demand for zinc will increase. Production and refining methods for zinc are also influencing prices as these processes are becoming ever increasingly cost-effective. This will increase the supply of available zinc and thus lower the price of this metal. Limited remaining deposits can cause difficulties on the supply of zinc in the future. In comparison to various precious metals and base metals, zinc has a lower return yield which is why very limited budget is spent on the exploration of new zinc deposits.

This may cause a deficit in the long term, which will eventually raise prices. A Zinc Futures Contract on the London Metal Exchange (LME) has the following specifications: Product Symbol Galvanizing - definition of galvanizing by The Free Dictionary Galvanizing - definition of galvanizing by The Free Dictionary Related to galvanizing: electroplating , cold galvanizing gal·va·nize tr.v. gal·va·nized, gal·va·niz·ing, gal·va·niz·es 1. To stimulate or shock with an electric current. 2. To arouse to awareness or action; spur: "The country was galvanized in the weeks and months after 9/11" (Davis Phinney). 3. To coat (iron or steel) with rust-resistant zinc. gal′va·ni·za′tion (-nĭ-zā′shən) n. gal′va·niz′er n. ThesaurusAntonymsRelated WordsSynonymsLegend: DOES ZINC HELP ACNE DOES ZINC HELP ACNE zinc Galvanized iron or steel, esp.

as the material of domestic utensils or corrugated roofs a bluish-white lustrous metallic element; brittle at ordinary temperatures but malleable when heated; used in a wide variety of alloys and in galvanizing iron; it occurs naturally as zinc sulphide in zinc blende The chemical element of atomic number 30, a silvery-white metal that is a constituent of brass and is used for coating (galvanizing) iron and steel to protect against corrosion coat or cover with zinc Zinc (from Zink), also known as spelter, is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. acne The occurrence of inflamed or infected sebaceous glands in the skin; in particular, a condition characterized by red pimples on the face, prevalent chiefly among teenagers Acne is a general term used for eruptive disease of the skin.

an inflammatory disease involving the sebaceous glands of the skin; characterized by papules or pustules or comedones (ACNES) The abdominal cutaneous nerve entrapment syndrome (ACNES) consists of pain caused by entrapment of the abdominal segmental nerves within the rectus abdominis muscle. Intercostal neuralgia appears to be a restricted form of ACNES. does zinc help acne - Blackmores Bio Blackmores Bio Zinc Zinc Treatment of Inflammatory Acne. It Does Not Help the Healing. The product. For health. Vitamin and mineral supplements. Good for wounds. Help wounds heal faster. The zinc in zinc Amino Acid Chelate reduce it for those with acne. Supplemented with vitamin B 6, vitamin and mineral needs. Just one tablet a day. Volume containing 90 tablets. The tablets contain 1. % US RDA. Zinc (as Zinc Amino Acid Chelate). 14.9 mg. 99.3. Magnesium (as magnesium phosphate). 18.6 mg. 07.04. Manganese (as Manganese Amino Acid Chelate). 2 mg. 57.1. Vitamin. 2500 international units.

50th. Vitamin B 6 (Chris Pine flower scene hydrogen chloride). 50 mg. In 2500. zinc in oyster Zinc- oyster (148.7 mg/100g serving) Zinc is critical to healthy male sex hormone and prostate function. Zinc Zinc ceiling does zinc help acne What it is:A fast-acting spot treatment that minimizes acne breakouts and promotes immediate healing of blemishes. What it is formulated to do:This product provides on-the-spot acne control the moment you feel a blemish developing. A powerful acne-fighting formula, it treats breakouts while promoting healing with anti-inflammatory ingredients that soothe and reduce redness. Its convenient size makes it easy to provide extra attention to a stubborn blemish anytime, anywhere. What it is formulated WITHOUT: - Sulfates- Synthetic Fragrances- Synthetic Dyes- Petrochemicals- Phthalates- GMOs- Triclosan What else you need to know: High performance ingredients, such as sulfur and salicylic acid, reduce the severity of acne blemishes while encouraging cell turnover. Zinc and licorice root extract provide anti-inflammatory benefits and help promote healing.

This product is dermatologist developed. Research results: 92 percent of users experienced a reduction in acne breakouts in just three days when used in combination with Murad Acne Complex(R) products (Clarifying Cleanser, Exfoliating Acne Treatment Gel, Skin Perfecting Lotion). Individual results will vary. IS ZINC GOOD FOR ACNE IS ZINC GOOD FOR ACNE Is Zinc Good For Acne good for (a period of time, an amount of exertion): safe to live or last so long, well able to accomplish so much. zinc The chemical element of atomic number 30, a silvery-white metal that is a constituent of brass and is used for coating (galvanizing) iron and steel to protect against corrosion Zinc (from Zink), also known as spelter, is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Galvanized iron or steel, esp.

as the material of domestic utensils or corrugated roofs coat or cover with zinc a bluish-white lustrous metallic element; brittle at ordinary temperatures but malleable when heated; used in a wide variety of alloys and in galvanizing iron; it occurs naturally as zinc sulphide in zinc blende acne an inflammatory disease involving the sebaceous glands of the skin; characterized by papules or pustules or comedones Acne is a general term used for eruptive disease of the skin. (ACNES) The abdominal cutaneous nerve entrapment syndrome (ACNES) consists of pain caused by entrapment of the abdominal segmental nerves within the rectus abdominis muscle. Intercostal neuralgia appears to be a restricted form of ACNES. The occurrence of inflamed or infected sebaceous glands in the skin; in particular, a condition characterized by red pimples on the face, prevalent chiefly among teenagers is zinc good for acne - New Chapter New Chapter Organics Zinc Food Complex Tablets, 60-Count Whole-Food Herbal Probiotic Nutrient Complex available in 60 tablet size ? Whole-Food Probiotic zinc to build resistance, support energy production and promote normal metabolism* ?

Peppermint/Stinging Nettle herbal extract combination provides trace nutrients to promote good digestion and normal metabolism* Probiotic NutrientsTM, exclusively from New Chapter®, are created by the two-stage culturing activity of nutritional yeast and three species of lactobacillus, acidophilus, bifidus, and rhamnosus. These beneficial probiotics culture the listed vitamins, minerals, and certified organic whole soy flour and food concentrates, creating 100% whole-food nutrients that are remarkably easy to digest and utilize, while simultaneously offering naturaly occurring phytonutrients such as soy isoflavones, beta glucans, bioflavonoids, SOD, glutathione, lipoic acid and enzymes. tivos are good for licking jen bought herself a tivo while in america. that bitch. =) Day 146~So be good for goodness sake! Day 146/365 Happy Holidays! Zinc Processing - definition of Zinc Processing by The Free Dictionary Zinc Processing - definition of Zinc Processing by The Free Dictionary (zĭngk) n. Symbol Zn A bluish-white, lustrous metallic element that is brittle at room temperature but malleable with heating.

It is used to form a wide variety of alloys including brass, bronze, various solders, and nickel silver, in galvanizing iron and other metals, for electric fuses, anodes, meter cases and batteries, and in roofing, gutters, and various household objects. US pennies minted after 1982 consist of a copper-clad zinc core. Atomic number 30; atomic weight 65.38; melting point 419.53°C; boiling point 907°C; specific gravity 7.134 (at 25°C); valence 2. See Periodic Table . tr.v. zinced, zinc·ing, zincs or zincked or zinck·ing or zincks To coat or treat with zinc; galvanize. [German Zink, possibly from Zinke, spike (so called because it becomes jagged in the furnace), from Middle High German zinke, from Old High German zinko.] zinc (zɪŋk) n 1.

(Elements & Compounds) a brittle bluish-white metallic element that becomes coated with a corrosion-resistant layer in moist air and occurs chiefly in sphalerite and smithsonite. It is a constituent of several alloys, esp brass and nickel-silver, and is used in die-casting, galvanizing metals, and in battery electrodes. Symbol: Zn; atomic no: 30; atomic wt: 65.39; valency: 2; relative density: 7.133; melting pt: 419.58°C; boiling pt: 907°C 2. (Metallurgy) informal corrugated galvanized iron [C17: from German Zink, perhaps from Zinke prong, from its jagged appearance in the furnace] ˈzincic, ˈzincous, ˈzincoid adj (zɪŋk) n., v. zincked zinced (zɪŋkt) zinck•ing zinc•ing (ˈzɪŋ kɪŋ) n. 1.

a ductile, bluish white metallic element: used in making galvanized iron and other alloys, and as an element in voltaic cells. Symbol: Zn; at. wt.: 65.37; at. no.: 30; sp. gr.: 7.14 at 20°C. v.t. 2. to coat or cover with zinc. [1635–45; < German Zink, perhaps derivative of Zinke(n) prong, from the spikelike form it takes in a furnace] zinc (zĭngk) Symbol Zn A shiny, bluish-white metallic element that is brittle at room temperature but is easily shaped when heated. It is widely used in alloys such as brass and bronze, as a coating for iron and steel, and in various household objects. Zinc is essential to the growth of humans and animals. Atomic number 30. See Periodic Table . Zinc How zinc is made - material, used, parts, components, composition, industry, machine, Applications Process Mining 1 Zinc ores are dug from underground mines using conventional blasting, drilling, and hauling techniques.

The ores occur as zinc sulfide (also called sphalerite), zinc carbonate (smithsonite), zinc silicate (calimine), and in compounds of manganese and iron (franklinite). Zinc ore is sometimes mined in conjunction with silver or lead ores. In addition to the ore itself, oil and sulfuric acid are required for the breakdown of the ores; and electricity, coke, or natural gas are needed to provide the heat energy for smelting. Froth flotation 2 Zinc can be produced by a process called froth flotation, which is also used for reduction of copper and lead ores. This process involves grinding the zinc ore to a fine powder, mixing it with water, pine oil, and flotation chemicals, and then agitating the mixture to "float" the zinc to the surface. A variety of chemicals are used to coat the important zinc particles and prevent them from becoming wetted by the water. Then air is injected, and the coated minerals attach themselves to the bubbles. The operation is performed inside a vat and agitated with an impeller.

The rotating impeller draws the air down the standpipe that surrounds the impeller shaft and dissipates it throughout the mixture or "pulp." The zinc rises to the top and the residue stays in the bottom of the pulp, since it cannot adhere to the bubbles. Automatic scrapers remove the mineral-laden froth containing the zinc. Filtering 3 The froth is filtered to remove the water and liquid oils. The paste-like remainder is mixed with lime and sent to a furnace. The furnace roasts the mixture at 2500°F (1371°C), which fuses the minerals into solid chunks called sinter. At this point, the material has been completely converted to zinc oxide. Smelting 4 The next reduction process uses a blast furnace to melt the prepared ore into its elemental components. The blast furnace is fueled by electricity, coke, or natural gas, which generate temperatures of up to 2200°F (1204°C). This, however, also generates carbon dioxide, which recombines with the zinc as it cools to re-form zinc oxide. To reduce this reformation, the zinc is sprayed with molten lead while it is still hot.

The lead, at 1022°F (550°C), dissolves the zinc and carries it to another chamber, where it is cooled to 824°F (440°C). At this temperature, the lighter zinc separates out of the lead and is drained off the top. The lead is reheated and returned to the blast furnace. Refining 5 Further metal improvement can be made by keeping the zinc molten and undisturbed for several hours. In this state, iron and other contaminants settle to the bottom, allowing the almost pure zinc to be carefully drawn off the top and cast into ingots. Alloying 6 Most zinc is alloyed with other metals before use to improve its properties. Alloying involves remelting and mixing the zinc with other metals in precise proportions. For example, approximately 4% aluminum is added to improve casting quality and die life in the die-casting process. Other added alloys are small amounts of titanium, copper, and magnesium. After alloying, the molten metal is poured into sow molds and ingot molds. Sows can weigh several thousand pounds, while ingots weigh about 45 pounds (20 kg).

Quality Control Metal alloys are inspected by a process called spectrographic analysis. The metal is burned under a protective cover using an electrical arc. The light emitted by the burning metal is passed though an apparatus much like a prism, which breaks the light into all of its individual colors. Every element has a different set of colors, or spectrum, which is like a fingerprint. Any foreign material will alter the spectrum, and in doing so show its unique color spectrum, identifying it. The computer in the spectrograph uses sensors to pick up these colors. The computer program then produces a printout that identifies each element in the spectrum and the concentration within the metal. Elements can be reduced or increased to alter the composition. The Future Because of the strength to weight ratio of zinc, its use by the automotive industry as a die casting has been diminishing in the past few years. Magnesium, aluminum, and plastics have taken over many zinc applications. The use of zinc to galvanize automobile body parts has been increasing, however. Many vehicles today are protected by zinc galvanizing which allows the manufacturer to offer extended warranties for body rust problems with new cars. Where To Learn More Periodicals Queneau, Paul B. and Jerome P. Downey.

"Secondary Zinc Production Minimizes Waste." Pollution Engineering, November 1994, pp. 42-44. Yates, Edward M. "Zinc: Major Mine Production Cuts in 1993." Engineering and Mining Journal, March 1994, pp. 19-21. — Douglas E. Betts Metal Profile: Zinc Metal Profile: Zinc By Terence Bell Updated October 31, 2015 Zinc is a lustrous bluish-grey metal that is primarily used to galvanize iron and steel in order to protect against corrosion . Also referred to as spelter, zinc is one of the most highly demanded non-ferrous metals with total global consumption falling behind only aluminum and copper . Properties: Density: 7.133 g/cm3 at 20°C Element Category: Transition metal Melting Point: 787°F (419°C) Boiling Point: 1665°F (907°C) Moh's Hardness: 2.5 Characteristics: Pure zinc is a hard and brittle, bluish grey metal that readily reacts with oxygen.

Ironically, it is zinc's 'weakness' - its low nobility - that is actually its most valued property and critical to most applications for the metal. Being one of the least noble of all common metals, zinc corrodes easily and, in an electrolytic environment, will become electropositive (anodic), thereby, protecting other, more noble metals from corrosive attack. By applying zinc to steel, in a process called galvanization, it works to protect the ferrous metal against rusting. Zinc has the lowest melting point of all transition metals aside from mercury and cadmium, allowing it - and many alloys containing the metal - to be die cast. Pure zinc, meanwhile, is soft enough to be formed, rolled or extruded. Zinc also readily alloys with other metals. Perhaps the most well-known zinc alloy , brass, combines the workability, corrosion resistance and aesthetic appeal of copper with the hardness and strength of zinc. The base metal is also diamagnetic and fair conductor of electricity. One unique distinguishing characteristic of zinc is that it creates a chime sound when bent, similar to tin cry.

Production: Nearly all zinc refined today (over 95 percent) is extracted from sphalerite (ZnS), otherwise known as zinc blende. Sphalerite ores generally contain between 5 and 15 percent zinc. To get this to a pure state that can be used by consumers, the metal must be separated, concentrated and refined into a pure metallic form. Either hydro-metallurgical or pyro-metallurgical processes can do this, however, over 90 percent of current production now originates from hydrometallurgical plants. Once mined, zinc ore is crushed into powder and separated from lead via froth flotation. Lead and other metals, such as silver , that may be present in the ore in recoverable quantities will be extracted and treated separately. The remaining concentrate will consist of between 1 to 15 percent zinc, but retain a high sulphur content (around 30 percent) that must be removed. This can be done by roasting the crushed ore at temperatures over 1652°F (900°C), producing zinc oxide (ZnO) and sulphur dioxide. More...

Applications: While primarily used to galvanize steel and iron in structural applications, zinc can also be found in a wide range of alloys that are used to produce everything from automobile parts to golf clubs. Zinc applications can be broken down into five general groups based upon the method and form of use: zinc - definition of zinc in English | Oxford Dictionaries Definition of zinc in English: zinc noun 1[mass noun] The chemical element of atomic number 30, a silvery-white metal which is a constituent of brass and is used for coating (galvanizing) iron and steel to protect against corrosion.

Example sentences ‘Most farmers are adding selenium, copper, zinc and iodine to their water supply.’ ‘A coating of zinc on steel can be used and the aluminum welded to it by the gas tungsten arc welding process.’ ‘Look for sunblocks and protective moisturizers with zinc or titanium dioxide.’ ‘A zinc rich paint coating protects the interior of the pipe.’ ‘Alloyed with tin, copper makes bronze, and combined with zinc, it makes brass.’ ‘He has been known to test his blood to regulate levels of zinc, magnesium and oxygen.’ ‘Bison meat contains many minerals but is highest in selenium, zinc, phosphorus, iron, copper and magnesium content.’ ‘It is very common for fireworks to contain aluminum, iron, steel, zinc or magnesium dust in order to create bright, shimmering sparks.’ ‘Coatings such as zinc and tin provide protection against corrosion.’ ‘These changes were associated with large increases in phosphorus, potassium, zinc, iron, manganese, and copper.’ ‘In the water samples, elevated levels of chromium, chlorine, molybdenum, and zinc were found in the MS cluster area.’ ‘Our own bodies contain several essential metals, such as zinc, copper and iron.’ ‘The primary use of zinc is in

 galvanizing other metals, especially iron and steel.’ ‘The atomic sizes of zinc and silver differ little from that of aluminum.’ ‘Plates can be made from a variety of metals, including zinc, copper, bronze and steel.’ ‘Fortified breakfast cereals with milk are an important source of iron, calcium, zinc, folic acid and B vitamins.’ ‘Minerals such as iron, zinc, copper, nickel, and other metals continue to be released from the vent as long as it remains active - usually one to two years.’ ‘The roof structure is of laminated wood, clad in silver-colored aluminum and zinc.’ ‘Soy beans are also a rich source of calcium, iron, zinc, phosphorus, magnesium, B-vitamins, omega - 3 fatty acids and fiber.’ ‘Connecting the steel to a higher potential metal, such as zinc, by a wire reverses the current and halts the rebar corrosion.’ 1.1[usually as modifier] Galvanized iron or steel, especially as the material of domestic utensils or corrugated roofs: ‘a zinc roof’ More example sentences ‘I had wanted to paint it, but was unable to quickly locate the zinc primer that would enable the paint to stick to the aluminum.’

 ‘High alloy zinc nickel deposits represent the highest level of performance even after deposit post forming and heating.’ ‘The structures will be unified by a massive aluminum and zinc roof bordered by a narrow overhang.’ ‘The wet area has a sink surrounded by a zinc countertop.’ ‘The refurbished zinc roof forms an arresting contrast with the cream tiled and rendered walls of the main building.’ ‘Beans pack a bigger shot of zinc than any other member of the veggie family; some (like baked beans) even rival the zinc content of red meat.’ ‘The older areas in the center of the city are often made up of mud and cement houses with corrugated zinc roofs.’ ‘Harvey's better idea was bullets cast of pure lead with a zinc base.’ ‘Keep the painted side of the bottle in contact with a corrugated zinc sheet and expose it to sunlight for six hours.’ ‘Modern materials are now often incorporated into building techniques, especially zinc sheets for roofs and cement to cover floors and walls.’ ‘Imported building material, such as the zinc sheets for roofing, is becoming increasingly important in the countryside.’ ‘It's made of a specially coated material covered with zinc anodes to ward off corrosion.’ ‘Rectangular houses with zinc roofs and concrete floors are common in villages

 and small towns.’ ‘Conceptually, the building can be read as a man-made landscape enveloped by a single undulating zinc roof like the horizon line.’ ‘Many people can afford corrugated zinc roofs on their homes.’ ‘Newer houses have walls made of adobe blocks or bricks, with roofs of corrugated zinc or cement.’ ‘She was a poor woman, and she lived in a fairly small board house with a zinc roof.’ ‘The floors are of wood or tile, and the roofs of zinc or corrugated iron.’ ‘Each is topped by an elaborate zinc roof with wide overhangs intended to reduce insolation.’ ‘They mark a long east-west colonnade that links a series of discrete rooms clad in sprayed earth and topped with curved zinc roofs.’ verb What is the American word for the British tea towel?

tea cozy What is the American word for the British trainers? loafers What is the American word for the British braces? suspenders What is the American word for the British lift? elevator What is the American word for the British flyover? overpass What is the American word for the British garden? guard What is the American word for the British mangetout? artichoke What is the American word for the British dust sheet? throw pillow What is the American word for the British dustbin? garbage can What is the American word for the British holiday? spring break You scored /10 practise again? Retry Metal Profile: Iron Metal Profile: Iron By Terence Bell Updated May 10, 2015 Iron's use by humans dates back about 5000 years. It is the second most abundant metal element in the earth's crust and is primarily used to produce steel , one of the most important structural materials in the world. Properties: Melting Point: 2800°F (1538°C) Boiling Point: 5182°F (2862°C) Moh's Hardness: 4 Characteristics: Pure iron is a silver-colored metal that conducts heat and electricity well.

Iron is too reactive to exist alone so it only occurs naturally in the earth's crust as iron ores , such as hematite, magnetite and siderite. One of iron's identifying characteristics is that it is strongly magnetic . Exposed to a strong magnetic field, any piece of iron can be magnetized. Scientists believe that the earth's core is made-up of about 90% iron. The magnetic force produced by this iron is what creates the magnetic North and South poles. History: Iron was likely originally discovered and extracted as a result of wood burning on top of iron containing ores. The carbon within the wood would have reacted with the oxygen in the ore, leaving a soft, malleable iron metal. Iron smelting and the use of iron to make tools and weapons began in Mesopotamia (present day Iraq) between 2700 and 3000 BC. Over the following 2000 years, iron smelting knowledge spread eastward into Europe and Africa during a period known as the Iron Age. From the 17th century on, until an efficient method to produce steel was discovered in the mid-19th century, iron increasingly used as a structural material to make ships, bridges and buildings.

The Eiffel Tower, constructed in 1889, was made using over 7 million kilograms of wrought iron. Rust: Iron's most troublesome characteristic is its tendency to form rust. Rust (or ferric oxide) is a brown, crumbly compound that is produced when iron is exposed to oxygen. The oxygen gas that is contained in water speeds up the process of corrosion . The rate of rust - how quickly iron turns into ferric oxide - is determined by the oxygen content of the water and the surface area of the iron. Salt water contains more oxygen than fresh water, which is why salt water rusts iron faster than fresh water. Rust can be prevented by coating iron with other metals that are chemically more attractive to oxygen, such as zinc (the process of coating iron with zinc is referred to as ' galvanizing '). However, the most effective method of protecting against rust is the use of steel. Steel: Steel is an alloy of iron and various other metals, which are used to enhance the properties (strength, resistance to corrosion, tolerance of heat etc.) of iron. Changing the type and amount of the elements alloyed with iron can produce different types of steel.

The most common steels are: Carbon steels, which contain between 0.5-1.5% carbon. These are the most common steels and are used for auto bodies, ship hulls, knives, machinery and all types of structural supports. Low alloy steels, which contain between 1-5% other metals (often nickel or tungsten ). Nickel steel is able to withstand high levels of tension and is, thus, often used in the construction of bridges and for making bicycle chains. Tungsten steels keep their shape and strength in high temperature environments and are used in impact, rotary applications, such as drill bits. High alloy steels, which contain 12-18% of other metals are only used in specialty applications due to their high cost. One example of a high alloy steel is stainless steel, which often contains chromium and nickel, but can be alloyed with various other metals as well. Stainless steel is very strong and highly resistant to corrosion. Production: Most iron is produced from ores found near the earth's surface. Modern extraction techniques use blast furnaces, which are characterized by their tall stacks (chimney-like structures).

The iron is poured into the stacks along with coke (carbon rich coal) and limestone (calcium carbonate). Nowadays, the iron ore normally goes through a process of sintering before entering the stack. This process forms pieces of ore that are between 10-25mm, which are then mixed with coke and limestone. The sintered ore, coke and limestone are then poured into the stack where is burns at temperatures of 1800°C. Coke burns as a source of heat and, along with oxygen that is shot into the furnace, helps to form the reducing gas carbon monoxide. The limestone mixes with impurities in the iron to form slag. Slag is lighter than molten iron ore, so it rises to the surface and can easily be removed. The hot iron is then poured into molds to produce pig iron or directly prepared for steel production. Pig iron still contains between 3.5-4.5% carbon, along with other impurities, and is brittle and difficult to work with. Various processes are used in order to lower the phosphorus and sulphur impurities in pig iron in order to produce cast iron.

Wrought iron, which contains less than 0.25% carbon, is tough, malleable and easily welded, but is much more laborious and costly to produce than low carbon steel. In 2010, global iron ore production was around 2.4 billion tonnes. China, the largest producer, accounted for about 37.5% of all production, while other major producing countries include Australia, Brazil, India and Russia. Applications: Iron was once the primary structural material, but it has long been replaced by steel in most applications. Nevertheless, cast iron is still used in pipes and to make automotive parts, such as cylinder heads, cylinder blocks and gearbox cases. Wrought iron is still used to produce home décor items, such as wine racks, candleholders and curtain rods. References:

Question: Which metal , with the atomic number 30, is used to coat iron or steel in the galvanizing process ?
Answer: ZINC