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.
Paul Alexander who spent more than 70 years living inside an iron lung has passed away.
In 1952 at the age of 6 paul was afflicted with polio, however this did not deter him from embracing each day to the fullest..
Despite being confine to the iron lung Paul pursued a career in law and...
Naomba nitoe salam kwa member wenzangu wa JF.
Kwa mara nyingine, leo nawaletea historia ya mwanamasumbwi bora wa kike wa muda wote, na wa uzito wote (The GOAT) Laila Ali au unaweza kumwita 'She bee stingin' ni mtoto wa King wa mchezo huo duniani Muhammad Ali 'The Greatest'.
Laila Ali alizaliwa...
Leo sitaki niseme mengi.Mtajionea wenyewe hapo chini
Iran unveils air defence systems as Middle East tensions soar
Saudi Arabia signs $3.2B deal for South Korean air defense systems
Saudi Arabian GP 2024: 3 international music stars will perform
katika makombora 10 ni moja linaweza kupenya mengine yanapanguliwa,
JE, Israel wakirusha hata kombora moja, Hezbollah wanaweza kulizia ? itakuwaje Israel ikirusha mamia ya makombora kwa mpigo kama wanavyofanyiwa na Hamas au Hezbolah ?
Hezbollaj wanarusha roketi za dola elf 2 (shilingi milioni...
Serikali imetoa taarifa kuhusu maendeleo ya hali baada ya maafa ya maporomoko ya tope, mawe, magogo na mawe kutoka mlima Hanang Wilayani Hanang Mkoa wa Manyara, ambapo imesema hadi kufikiasaa 6:00 mchana leo December 08,2023 idadi ya vifo imefikia 80 (Watu wazima ni 48 wakiwemo Wanaume 19 na...
Tangu vita vianze upya baada ya ukimya wa siku 7 wakati wa kubadilishana mateka Hamas imeendelea kurusha maroketi ya masafa marefu kutokea ndani ya Gaza ambayo yanaufikia mji mkuu wa Israel wa Tel Aviv.
Kwa mujibu wa Allan Fisher ,mpashaji habari wa aljazeera makombora kadhaa yaliyorushwa hapo...
Vita kumbe bado viko hatua za mwanzo sana na yajayo yatafurahisha.
Inashangaza sana nchi za kiarabu kumuogopa simba ambaye ameshachoka kujitetea
Habari mpya ni kwamba jeshi la Israel huenda likainunua upya mitambo yake ya Iron dome iliyoiuzia au kuitoa kwa mshirika wake US.
Hali hiyo si jambo...
Hapo Jana usiku Hezbullah na HAMAS walifanya mashambulizi ya rocket na makombora,na kwa asilimia kubwa yakapiga makazi ya miji kadhaa ya Israel kama vile Ashdod,Tel aviv na kwingineko huku mfumo wa Ulinzi wa kuzuia makombora ikishindwa kuinterrcept na baadala yake ikawa inayasamabaza kwa...
Siku zote nimekuwa nasema kuwa demokrasia ni mfumo wa hovyo sana wa utawala. Sasa kuna mwanazuoni mmoja aliobserve kitu kimoja. Kwanza kwa kifupi oligarchy ni mfumo wa utawala wa matajiri wachache.
Matajiri wachache ndiyo wanaendesha nchi. Sasa kutika observation zake mwanazuoni huyo aligundua...
Iron Dome ni mfumo wa ulinzi wa kisasa wa anga ambao ni bora na mathubuti kwa dunia ya leo uliotengenezwa na Israel kwa msaada kiasi kutoka Marekani kwa lengo la kulinda dhidi ya makombora yaliyofyatuliwa kutoka kwenye maeneo ya adui.
Mfumo huu ulianza kutumika rasmi mwaka 2011 na umekuwa...
Haya aliyasema Plato kama picha inavyoonesha hapa chini.
Iron ladies and Iron boys akina Nape and Chawa Co. Ltd ndio wanaongoza taifa lazima kuwa na majanga kama haya.
Hata Magufuli alikuwa Iron Boy!
johnthebaptist
Waziri wa Ulinzi wa Ukraine amesema kuwa mfumo wa Ulinzi wa anga wa Israel maarufu kwa jina la Iron Dome hauwezi kuhimili kuzuia makombora ya Urusi nchini Ukraine.
Waziri huyo aliyeshuhudia na kutesti nguvu ya makombora ya Urusi anasema kuwa mfumo huo wa Iron Dome umeundwa kwa ajili ya kuzuia...
The controversial decision to approve $1 billion for Israel’s Iron Dome missile system has drawn flak from a cross-section of people, from politicians to activists to journalists in the US.
It has also exposed deep political and ideological fault lines in the Democratic Party, with many senior...
Kumekuwa na upotoshaji mkubwa sana unaofanywa maksudi na media na sijui kwanini.
Mfano mpaka sahivi hamas amesharusha makombora zaid ya 1000+ Israel lakin kinachowasaidia Israel ni kuwepo kwa mfumo wa iron dome defense system.
Hamas anaporusha Yale makombora yake achagui, tofauti na Israeli...
Haujambo Mwana Jamvi, Heri na hongera sana kwa sikukuu ya Eid-Al-fitr. Kwa niaba yangu binafsi nakutakia sherehe njema, ikawe heri na amani kwa upande wako. Eid Mubarak!!!!
Mwaka 2006 viliibuka vita kati ya Israel na Lebanon. Lebanon ( Hezborah) ilivurumisha maelfu ya makombora katika anga ya...
Kwa mara nyengine tena Israel imekiri kuzidiwa nguvu na idadi ya vikombora vinavyorushwa na wanamgambo wa makundi tofauti kutoka Gaza. Taarifa hizo zimekuja katikati ya muendelezo wa machafuko makubwa yanayoendelea eneo la Jerusalem tangu kuanza kwa mwezi mtukufu wa Ramadhan.
Katika mapigano...
Makamu wa Rais wa Jamhuri ya Muungano wa Tanzania katika awamu ya tano, Samia Suluhu Hassan anaapishwa leo kuwa Rais wa Jamhuri ya Muungano wa Tanzania awamu ya 6 kufuatia kifo cha Rais John Joseph Pombe Magufuli, Rais wa awamu ya 5 wa Jamhuri ya Muungano wa Tanzania.
WASIFU WA SAMIA SUHULU...
VP Samia for Uganda next week to seal pact on crude oil pipeline
VICE President Samia Suluhu Hassan is on Monday expected to leave the country for Uganda to sign another vital agreement for the official beginning of the construction of the crude oil pipeline from Hoima in Uganda to Tanga in...
Niaje waungwana
katika pitapita zangu nimekutana na pasi za umeme ambazo functioning yak ni baada ya kucharge kama simu.
Je, ni wapi kwa hapa bongo ntazipata, na bei yake ipo je?
Those who have been elected or appointed to occupy some offices in government or parliament tend to fake their smiles and give satirical praises to Magufuli.
And some go beyond by speaking blasphemy to a point of exalting Magufuli above God.
While all these are done so as to please him, but...
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