iron

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, 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 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 1500 °C or higher, about 500 °C higher than what is enough to smelt copper. Humans started to master that process in Eurasia only 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, inox, cast iron and special steels are by far the most common industrial metals, because of their high 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.
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.

View More On Wikipedia.org
  1. H

    Replace cast iron

    I would like to replace the cast iron branch with plastic but am not sure how far below the floor level I will find the point where the branch spigot enters the female fitting. The floor is in a garage and there is a room below that I cannot access therefore all work has to be done from above...
  2. P

    Iron pipework

    Hi I need to T into an iron pipe. Both sides of the proposed T are attached to stuff that will prevent the pipe being screwed into a fitting, even if I get the tools to thread the pipe ends. How do you connect into this stuff? In copper it would take 30 mins.
  3. M

    Do I really need a Combi-boiler to replace my existing boiler in A1 condition?

    Hi just joined the forum. Looking forward to getting some experienced opinions here. Really quite desperate to get 2nd opinions etc.. We have a house built in 1934. Our water inlet pipe was changed to the blue plastic about 2 years ago. We had a disconnected water softer when we moved in and...
Top Bottom