One was a level metal paddle in which the user would beat the clothes in the hope the pounding would remove the wrinkles. The ancient Chinese used a scoop that was heated with hot coal or sand and would rub it over clothing to smooth wrinkles.
What modern customers would identify as an iron first appeared in Europe in the s. The flatiron, as it was called, was simply a smooth piece of metal affixed to a handle.
The iron would be heated over flames until sufficiently hot, at which time it would be picked up with an insulated glove. A layer of cloth would cover the article of clothing to prevent soot from the iron from staining the finished garment. Once the flatiron cooled, it would be reheated and the process repeated. Besides smoothing wrinkles, ironing served another important function, killing germs in clothing and reducing mildew. It took about two centuries for the next significant improvement to the flatiron.
The "box iron" was composed of a flat-bottom box and a handle. All such documents and related graphics are provided "as is" without any representation or endorsement made and warranty of any kind, whether expressed or implied, including but not limited to the implied warranties of fitness for a particular purpose, non-infringement, compatibility, security and accuracy.
In no event shall the RSC be liable for any damages including, without limitation, indirect or consequential damages, or any damages whatsoever arising from use or loss of use, data or profits, whether in action of contract, negligence or other tortious action, arising out of or in connection with the use of the material available from this Site. Nor shall the RSC be in any event liable for any damage to your computer equipment or software which may occur on account of your access to or use of the Site, or your downloading of materials, data, text, software, or images from the Site, whether caused by a virus, bug or otherwise.
Jump to main content. Periodic Table. Glossary Allotropes Some elements exist in several different structural forms, called allotropes. Glossary Group A vertical column in the periodic table. Fact box. Glossary Image explanation Murray Robertson is the artist behind the images which make up Visual Elements.
Appearance The description of the element in its natural form. Biological role The role of the element in humans, animals and plants. Natural abundance Where the element is most commonly found in nature, and how it is sourced commercially. Uses and properties. Image explanation. The image is of the alchemical symbol for iron.
The symbol is shown against a rusty mild steel plate. Iron is an enigma — it rusts easily, yet it is the most important of all metals. Most is used to manufacture steel, used in civil engineering reinforced concrete, girders etc and in manufacturing. There are many different types of steel with different properties and uses. Ordinary carbon steel is an alloy of iron with carbon from 0. Alloy steels are carbon steels with other additives such as nickel, chromium, vanadium, tungsten and manganese.
These are stronger and tougher than carbon steels and have a huge variety of applications including bridges, electricity pylons, bicycle chains, cutting tools and rifle barrels. Stainless steel is very resistant to corrosion. It contains at least Other metals such as nickel, molybdenum, titanium and copper are added to enhance its strength and workability.
It is used in architecture, bearings, cutlery, surgical instruments and jewellery. It is used for pipes, valves and pumps. It is not as tough as steel but it is cheaper. Magnets can be made of iron and its alloys and compounds. Iron catalysts are used in the Haber process for producing ammonia, and in the Fischer—Tropsch process for converting syngas hydrogen and carbon monoxide into liquid fuels. Biological role. Iron is an essential element for all forms of life and is non-toxic.
The average human contains about 4 grams of iron. A lot of this is in haemoglobin, in the blood. Haemoglobin carries oxygen from our lungs to the cells, where it is needed for tissue respiration. Humans need 10—18 milligrams of iron each day. A lack of iron will cause anaemia to develop. Natural abundance. The core of the Earth is thought to be largely composed of iron with nickel and sulfur.
The most common iron-containing ore is haematite, but iron is found widely distributed in other minerals such as magnetite and taconite.
Commercially, iron is produced in a blast furnace by heating haematite or magnetite with coke carbon and limestone calcium carbonate. Around 1. Help text not available for this section currently. Elements and Periodic Table History. Iron objects have been found in Egypt dating from around BC.
They contain about 7. The Iron Age had begun. Some kinds of iron were clearly superior to others depending on its carbon content, although this was not appreciated.
Some iron ore contained vanadium producing so-called Damascene steel, ideal for swords. This explained how steel, wrought iron, and cast iron, were to be distinguished by the amount of charcoal carbon they contained. The Industrial Revolution which began that same century relied extensively on this metal.
Atomic data. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom. Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity.
Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Supply risk. In a study of more than 1, Finnish men ages 42 to 60 years, published in published in the journal Circulation, researchers found a link between high levels of iron and increased risk of heart attack.
In a more recent study , published online in January in the Journal of Nutrition, researchers found that heme iron, found in meat, increased the risk for coronary heart disease by 57 percent, but no such association was found between non-heme iron and coronary heart disease risk. Interestingly, recent research has also linked the accumulation of iron in the brain to Alzheimer's disease. In a study published in August in the Journal of Alzheimer's Disease, researchers found that the amount of iron in the hippocampus — an area of the brain associated with the formation of memories — was increased and associated with tissue damage in the hippocampus area in people with Alzheimer's disease, but not in healthy older people.
Iron deficiencies have also been linked with depression, according to a study published in the Journal of Psychiatric Research by a group of Australian researchers who were trying to find a link between genetics, iron levels and depression, especially with teenagers.
The researchers found that although there is a link between iron levels in the bloodstream and measure of depression, there is no evidence for a genetic relationship between the two. The researchers used data available from twin studies and looked at a variety of factors while comparing teenaged twins to adult twins.
The link between iron levels and depression is most likely to be observed during periods of time when the body requires higher amounts of iron such as during growth spurts. A article published in the European Journal of Nutrition by a research group from Iran described a study in which iron supplements were given to new, non-anemic mothers with postpartum depression PPD.
A group of 70 women began the double-blind trial one week after giving birth and PPD symptoms were compared six weeks later. Iron has been known to humankind since about B.
Its name is derived from the Anglo-Saxon version, which was "iren. If you're perusing a pharmacy and happen to see iron supplements, you will notice that most of their names are "ferrous" something-or-other such as sulfate or gluconate. Anytime you see the word "ferrous" or "ferric" in a chemistry context, you should immediately recognize that iron is being discussed; "ironic," though a splendid and useful word, has no role in the world of physical science.
Iron abbreviated Fe is classified as a metal not only for everyday purposes but also on the periodic table of the elements see Resources for an interactive example. This probably comes as little surprise, but in fact, metals outnumber nonmetals in nature by a wide margin; of the elements humans have discovered or created in laboratory settings, 88 are classified as metals.
Atoms, as you may already know, consist of a nucleus containing a mixture of protons and neutrons of roughly equal mass surrounded by a "cloud" of nearly massless electrons. Protons and electrons carry a charge of equal magnitude, but protons' charge is positive while that of electrons is negative. Iron's atomic number is 26, meaning that iron has 26 protons and 26 electrons in its electrically neutral state.
Iron possesses some formidable physical properties. It has a density of 7. Density is mass per unit volume; water's is defined as 1. Iron is a solid at 20 degrees Celsius 68 F , generally considered "room temperature" for chemistry purposes. Its melting point is an extremely high C F , while its boiling point — that is, the temperature at which liquid iron begins to evaporate and become gas — is a scorching C F.
It is no wonder, then, that in metalworking, the kinds of furnaces used must be extraordinarily powerful indeed. Iron, by mass, is the fourth-most-abundant element in the Earth's crust.
Iron's total share of Earth may be considerably greater, however, given that the planet's molten core is believed to consist chiefly of liquefied iron, nickel and sulfur. When iron is extracted from the ground in mining operations, it is in the form of ore, which is elemental iron mixed with one or more types of rock.
The most common type of iron ore is hematite, but magnetite and taconite are also significant sources of this metal.
0コメント