Iron Definition and 517 Threads

Iron () is a chemical element with symbol Fe (from Latin: 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 1,500 °C (2,730 °F) or higher, about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia by about 2000 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 the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels are by far the most common industrial metals, because of their mechanical properties and low cost.
Pristine and smooth pure iron surfaces are mirror-like silvery-gray. However, iron reacts readily with oxygen and water to give brown to black hydrated iron oxides, commonly known as rust. Unlike the oxides of some other metals, that form passivating layers, rust occupies more volume than the metal and thus flakes off, exposing fresh surfaces for corrosion. Although iron readily reacts, high purity iron, called electrolytic iron, has better corrosion resistance.
The body of an adult human contains about 4 grams (0.005% body weight) of iron, mostly in hemoglobin and myoglobin. These two proteins play essential roles in vertebrate metabolism, respectively oxygen transport by blood and oxygen storage in muscles. To maintain the necessary levels, human iron metabolism requires a minimum of iron in the diet. Iron is also the metal at the active site of many important redox enzymes dealing with cellular respiration and oxidation and reduction in plants and animals.Chemically, the most common oxidation states of iron are iron(II) and iron(III). Iron shares many properties of other transition metals, including the other group 8 elements, ruthenium and osmium. Iron forms compounds in a wide range of oxidation states, −2 to +7. Iron also forms many coordination compounds; some of them, such as ferrocene, ferrioxalate, and Prussian blue, have substantial industrial, medical, or research applications.

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  1. E

    Exploring the Effects of DC and AC Voltage on Iron Piece Movement

    Hello guys, I want to know if I apply a DC voltage to the wire winding then what will happen to the iron piece and why? What if the voltage happens to be AC?? I think that the iron piece will move but how and why, I am not sure... Thanks for any help
  2. M

    Question: Can elements above iron actually be clusters of smaller elements?

    Hello, I would like to ask if elements of higher atomic number than iron might actually be clusters made up of smaller elements? Is there any evidence that rules out this possibility? The reason I am guessing that elements below iron are discrete is because of the theory that iron has its...
  3. E

    Distinguish Iron (II) Chloride vs Iron (II) Sulfate | Chemistry Homework Help

    Hi I need help with my chemistry homework. I'm stuck on the following questions 1. Very dilute solutions of iron(II) chlodie and iron (II) sulfate have similar colours. Explain how you can distinguish solutions of these compounds. Give full details of the tests you can carry out as well as...
  4. A

    Double-slit experiment with magnets and iron projectiles

    Hi, I am not sure if this kind of experiment has been performed before. If so, great, I would love to see the results. Anyway, here goes. The double-slit experiments with photons, electrons and even...
  5. G

    Calculating Fraction of Electrons Removed from Iron Ball

    Homework Statement A 2.0 mm diameter iron ball is charged to +48 nC. What fraction of its electrons have been removed? The density of iron is 7,870 kg/m3. Homework Equations Q = Ne; N = number of atoms in 1 mole, e is atomic charge, Q = point charge N = Avagadro's Constant =...
  6. P

    Molten iron can not be magnetized

    Hi everyone. It is my(perhaps wrong) understanding that molten iron can not be magnetized nor attracted to a magnet. Is this true? If so, how can the Earth's magnetic field be attributed to molten iron at its core? This confuses me, likely due to my ignorance. Thanks...
  7. T

    Hollow iron spherical shell submerged in water, find the inner diameter

    Homework Statement A hollow spherical iron shell floats almost completely submerged in water. The outer diameter is 66.0 cm, and the density of iron is 7.87 g/cm3. Find the inner diameter. Homework Equations Fb=MG 4/3pir^3=Vsphere The Attempt at a Solution Not sure where to...
  8. S

    [Chemistry] Effects of iron (III), and iodine on esters

    More specifically, on acetylsalicylic acid (both crude/made in class, and commercial/store-bought), and salicylic acid. Please hang with me, I'll get to my question in a second. I did these tests: Crude aspirin w/ iron (III): Translucent, light peach in colour Crude aspirin w/ iodine...
  9. W

    How Do Gymnasts Balance Forces During an Iron Cross?

    Gymnast pictured below performing an Iron Cross has a mass of 65.00 kg. Assume that the forces in the cables are symmetric and that he is in static equilibrium. A. Draw a complete free body diagram of the gymnast (just him – he is the system). B. Calculate the vertical and horizontal...
  10. A

    Moose family welcome at Bærum Iron Works

    In the nowadays posh Oslo suburbia of "Bærums Verk" (where there previosly was a an iron works plant, founded in 1610), a moose family, on the third year in a row, has become a welcome sight. This article has a few photos of them...
  11. A

    Why is the Raman spectrum for iron oxide not showing a signal?

    RAMAN spectrum of iron oxide ! Dear every one! I have just got a new raman spectrometer to study the corosion of metals. i tested it on liquids (alcool, benzene, solvant ...) it works very well. i did also experiments on coal and carbon, perfect ! but when i tested on iron oxide .. i got no...
  12. M

    What is the Lattice Constant of Iron?

    Homework Statement The density of bcc iron is 7900 kg/m3, and its atomic wieght is 56 amu. Using this information, calculate the lattice constant of iron's cubic unit cell and the interatomic spacing (i.e. nearest neighbor distance). Homework Equations The Attempt at a Solution...
  13. S

    Why does ferrous iron make 6 covalent bonds?

    Hello everyone, Is their simple reason for this. Like how there must be 8 electrons in outer shell,I know that is very basic and probably not applicable, or is this something to do with sub shells etc. Also in billirubin metabolism. Why do red blood cells produce hemin which is iron in...
  14. J

    Fictional iron chemical reactions

    I am a mechanical engineer who is writing a science fiction novel where a means has been discovered to temporarily reduce the mass of the nucleus of certain 56Fe atoms. When a certain field is applied to the iron, it gets lighter. When the field is removed, the iron regains its original mass...
  15. V

    Why Were Copper Tools Developed Before Iron Tools?

    1. Homework Statement 10) Both iron (III) oxide and copper (IV) oxide are mined for use as primary ores in the production of pure iron and copper respectively. Historically, the earliest use of copper tools appears to be around 4500 BC. Iron tools appear much later; European artifacts have...
  16. C

    The Magnetic Attraction of an Iron Nail

    Why does an iron nail always get attracted to a bar magnet? You think one side would attract it and on side would repel it, Is this because When I bring the magnet close to the nail does it causes the domains to flip so it attracts it, Is this similar to why a neutral object gets attracted to a...
  17. M

    Spectrophotometry: Iron in Vitamin tablets and Absorbance

    This is the experiment that I did in class, please read the whole thing before posting: http://www.chem.uic.edu/fetzer/chem222/Exp_19.pdf How do I calculate the molarity of Fe(o-phenanthroline) in each solution? So I was thinking of doing this: According to the pdf there are 2.5 grams of...
  18. H

    Fusing Iron Nuclei: Ignition Temperature

    I am aware that fusing two iron nuclei together is highly endothermic. But at what temperature does it begin. Does anybody have a clue? I know that fusing two hydrogen nuclei begins at 10 to 14 million Kelvins and that helium fusion begins at 100 million Kelvins. It wouldn't surprise me that...
  19. I

    Determination of iron purity by redox reaction

    Hi just wondering if you could help, I've stumbled across an example question where the iron purity is meant to be above 80% when 8H+ + 5Fe2+ + MnO4- → 5Fe3+ + Mn2+ + 4H2O 15cm3 is titrated and concentration of potassium permanganate used is 0.02M So far I have worked out Number...
  20. A

    News Latin America under the iron boot. Does USA people know about that?

    Interesting documental about how Latin America suffered from anti-communism and how is still under threat. This parts talks about my country El Salvador. http://www.youtube.com/watch?v=x5NmZ-PdwIo&feature=related An this is part 1 if you wana see the whole documental. This...
  21. S

    Is Iron (III) Carbonate Really Insoluble?

    Homework Statement Basically, I missed a quiz question that had to do with solubility. According to the instructor's own rules AND everything I have read online, iron (iii) carbonate is insoluble. Homework Equations The Attempt at a Solution
  22. D

    Creation of elements heavier than iron

    Sorry if this question is too elementary (no pun intended) for this forum. If stellar fusion of iron takes more energy than it produces, how are heaver elements formed? Cheers, JP
  23. M

    Why is it iron 2 and not iron 3?

    Why is it iron 2 and not iron 3? Hi all Upon the reaction of Hydrochloric acid with Iron.. the following equation represents the reaction: Fe + 2HCl -------> FeCl2 + H2 Why isn't the product FeCl3? I don't understand what makes it not possible for iron to form this chloride salt...
  24. G

    Helmholtz Coils and Iron Cores

    Hi, I'm doing a project that involves the use of Helmholtz coils. We have coils and can calculate the magnetic field produced using the standard equation and taking everything into consideration. I know we can boost the magnetic field strength of the coils by introducing and iron...
  25. A

    Magnetic Flux with iron filings

    Hi all this is my first post. I would like to see magnetic flux is there anyway I could do this I remember at school many years ago using iron filing. I would like to see the results of magnetic shielding
  26. M

    Can the Nature of Reactants Predict Reaction Rates?

    So if a reaction involves Fe2+ and the same reaction involves Fe3+, which one would occur at a faster rate? I know that the nature of the reactants has to due something with this difference in the rate of the reaction but I'm not sure how to explain it. what about C2O42- (oxalate) and 2CO2...
  27. M

    Iron Ball in Desert: Exploring Equilibrium and Infinity Levels

    Let assume a desert with very deep sand and an iron ball on the ground level. Due to small perturbations (wind, small earthquakes, etc.) the iron ball will sinking down. Is there an equilibrium level, or the iron ball will sink down to "negative infinity level"?
  28. R

    Imaginary Field Lines vs True Iron Filings

    My (high school, gah!) textbook gives an experiment: I take a straight current carrying conductor, a cardboard sheet is placed perpendicular to the conductor, so that the conductor passes straight through the sheet, remains perpendicular. Then I use a salt sprinkler to sprinkle iron filings on...
  29. rrw4rusty

    Bringing iron asteroids down to Earth?

    Hi, I'm writing a science fiction story and in the future we are having to bring iron asteroids down to Earth. These asteroids are 1 to 3 miles in diameter and shaped charges brake up the asteroid and push it down into the atmosphere in such a way that the house size chunks land in an...
  30. S

    Amount of iron in the solar system

    Hi everyone Does anyone know of any source where the total amount of iron in the solar system has been estimated? Free iron, isotopes, oxides, etc. I've been reading here and there about element abundance on Earth and in the cosmos, and am curious if solar percentage of iron is...
  31. S

    Calculating Weight Savings of Aluminum Engine vs Cast Iron

    I've never taken physics, and I'm not even sure this is physics. :S On the hint it mentions, think of freshmen physics, but I honestly have no clue. Could someone help me out on how to even start this problem? Estimate the weight savings if a typical automobile engine (100 kg) is made of...
  32. M

    Extraction of iron on a match head

    Hi Please look at this link. It is only very brief. It describes how to extract iron from iron oxide on a match head. My questions are: where does the carbon come from in this equation Iron(III) oxide + carbon → iron + carbon dioxide 2Fe2O3(s) + 3C(s) → 4Fe(s) + 3CO2(g) Is it...
  33. Crowxe

    Trapping Iron Plate Motion Using Magnetic Shield

    An iron plate would glide through magnetic field lines from the more separated towards the more condensed of a permanent magnet. If we use a magnetic shield to make a trap where that iron plate finds itself in dead area (no magnetic field lines) then it would continue the motion it gained...
  34. Q

    Discover the Inner Workings of a Steam Iron's Water Pump

    How does the water pump inside a steam iron work?
  35. V

    The hilarious phyiscs of Iron Man

    (skip this paragraph if you just want the math) I had some free time today, so I thought I'd toy with the impossible hilarity of the Arc Reactor from the Iron Man films. My first line of calculation was on the magnetic field that would be generated if 1/10th of the power output (3 gigawatts!)...
  36. L

    Iron Fusion Reactors: Exploring Controllable States and Optimal Temperatures

    If iron is the last element to undergo fusion wouldn't it be expected to be at a controlled state. Ie: if the pile wants to go toward Hydrogen, bump up the fusing protons. If it to go beyond the Iron tipping point toward Uranium, adsorb protons. From the Binding Energy Curve, the reactor may be...
  37. S

    Heat exchange involving phase change, hot iron into water ->steam,

    Homework Statement I have been working on a University Physics thermodynamics problem for over a week now, day and night. I've consulted two physics PhDs, posted on Yahoo Answers (nobody took the bait) and I'm still stuck. I just wasted an hour and a half carefully posting my problem and...
  38. S

    Why does total iron binding capacity increase in anaemia?

    Hello everyone, In anameia related to iron, plasma tranferring increases and iron decreases. How does this increase the total iron binding capacity of the enzyme. If I draw a sample of blood, there would be some transferrin enzymes in excess lowering iron binding capacity right? Thanks :smile:
  39. T

    The Swinging Sticks from Iron Man 2 in action

    http://www.youtube.com/watch?v=ibFtijBf3zE&feature=related Please visit that website.. Is that think include of prepetual motion? Have some one founded prepetual motion formula? Could you explain to me, how that works?and how to make it?
  40. N

    Iron UV Spectrometer: Absorption in UV Radiations

    what is the absorption spectrum in UV radiations of iron?
  41. P

    Nerd Rage: Iron Man 2 and Scientific Advances

    Has anyone seen the part of Iron Man two where they combine the major scientific advances of the past centruy into a single scene where he makes a new element? For those who haven't, I will summarise; - He builds a particle accelerator in his front room showing no evidence of large...
  42. S

    Industry prices for galvanized iron pipes and labor?

    I have to put a spreadsheet together which tells me the most mechnically effecient and cost efficient configuration of a pump, piping, values, etc. Where can I find industry pricing for galvanized iron pipes and labor costs? thanks
  43. P

    Redox titration (calculating percent iron in sample)

    Homework Statement A mass of iron ore weighing 0.2792g was dissolved in dilute acid and all the iron was converted to Fe2+(aq). The iron II solution required 23.30ml of 0.0194M KMnO4 for titration. Calculate the percentage of iron in the ore.Homework Equations Wrote out my redox reactions...
  44. Q

    Why is iron magnetic and copper is not?

    Why is iron magnetic and copper is not?
  45. FeDeX_LaTeX

    Why are Iron, Cobalt and Nickel Magnetic?

    Hello; Why are only iron, cobalt and nickel magnetic, and not any other material? Is it due to their unique electron configurations, or due to something else? Thanks.
  46. J

    Research question about magnetic properties of iron

    Hello, I have recently been tasked with finding the permeability of iron at a frequency of 10 kHz. I have never done research before, this is my first time, I been looking all over the internet (IEEE, elsevier, ScienceDirect, etc...) for anything that might give me information on the subject...
  47. F

    Iron core for Electrostatic coil

    I am just an electrician doing experimental work with a Stubblefield coil. From what I've read the most common steel is 1018. If Stubblefield used a common bolt I assume this would fall into the 1018 realm. Would the 1018 iron core be better cold rolled or hot rolled for the magnetic collapse as...
  48. R

    Creating an Air Flow Meter Using an Iron Heating Element

    Homework Statement i am trying to make an air flow meter using an heating element which i got from an iron..basically i have thought of inserting the element into a duct through which i will pass air using a blower,to connect the element with a 12v supply in series with a ammeter...thn i...
  49. D

    Primary winding and secondary winding wraped around a iron core

    I got a few questions about transformers.. I understand there is a primary winding and secondary winding wraped around a iron core. Now for the primary connection - take 7.2kv 1 phase line and connect it to one side of the winding and take ground (earth) to the other winding end. On the...
  50. H

    Removing cement-like substance from a white-cast iron

    Hi all I have kind of an odd question, it has been quite hard to find an answer for. I'm doing a thesis comparing wear rates and patterns in low stress sliding abrasion between field conditions and labratory-based tests. The field trial uses a quarry 'pugmill', which is essentially a...
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