Chromium, da wani sinadari: description, Properties, kuma faye hali na dabara

Chromium - sinadari da atomic lambar 24. Wannan wuya, m, karfe-m karfe wanda yake da goge, da kuma ba tarnish. Amfani a cikin gami kamar bakin karfe, da kuma yadda wani shafi. jikin mutum na bukatar a kananan adadin trivalent chromium domin sugar metabolism amma Kr (VI) ne sosai guba.

Daban-daban chromium mahadi kamar chromium oxide (III) da kuma gubar chromate, suna haske launin da ake amfani a paints da pigments. Ruby ja launi saboda gaban wannan sinadari. Wasu abubuwa, musamman potassium dichromate da sodium oxidants aka yi amfani da hadawan abu da iskar shaka hanyoyin gudanar da mahadi, kuma (da sulfuric acid) for tsaftacewa glassware. Bugu da kari, chromium oxide (VI) da ake amfani da a samar da Magnetic tef.

Gano da kuma etymology

Tarihi na samu na da wani sinadari ne chromium. A 1761, Johann Gottlob Lehmann samu a cikin Ural duwãtsu orange-ja ma'adinai, da kuma kira shi "Siberian ja-gora." Ko da yake an yi kuskure gano a matsayin wani gubar fili da selenium, da baƙin ƙarfe, da kayan shi ne ainihin wani gubar chromate sinadaran dabara PbCrO _4. Yau ya aka sani a matsayin mai ma'adinai krokont.

A 1770, Peter Simon Pallas ziyarci wurin da Lehman sami wani ja-gora ma'adinai da cewa yana da matukar amfani, Properties na pigment a Paints. A amfani da Siberian ja-gora a matsayin Paint tsiwirwirinsu m ci gaba. Bugu da kari, da haske rawaya launi na krokonta zama gaye.

A 1797, Nicolas-Lui Voklen samu samfurori da ja-gora tama. Krokonta da hadawa shi tare da hydrochloric acid da aka cro ₃ oxide. Chromium matsayin wani sinadari da aka ware a 1798. Vauquelin samu shi ta gasa da oxide da gawayi. Shi ma iya gane burbushi na chromium a duwatsu masu daraja kamar yaƙutu da zumurrudu.

A 1800s kuma Kr yafi amfani a Paint da fata salts. Yau 85% na karfe amfani a cikin gami. Sauran da ake amfani a cikin sinadaran masana'antu, da yi na refractories da foundry masana'antu.

Pronunciation chromium sinadari yayi dace da Greek χρῶμα, ma'ana "launi", saboda a jam'i na launin mahadi wanda za a iya shirya daga barinta ne.

Mining da kuma samar da

Sinadarin samar daga chromite (FeCr ₂ Ya _4). Game da rabi na wannan tama aka mined a Afirka ta Kudu. Bugu da kari, Kazakhstan, India da kuma Turkey, akwai manyan kera. Bincika adibas na chromite isa, amma suna geographically mayar da hankali a Kazakhstan da kuma kudancin Afirka.

A adibas na 'yan qasar chromium karfe ne rare, amma sun wanzu. Alal misali, an samar a tawa "Nasara" a Rasha. Yana da wani kimberlite bututu mai arziki a cikin Diamonds, da kuma rage yanayi taimaki nau'i na m chromium da lu'ulu'u.

Domin masana'antu samar na karfe chromite tama da aka bi da tare da wani zubi Alkali (sodium hydroxide, NaOH). Wannan suranta sodium chromate (Na ₂ cro _4), wanda an rage tare da carbon zuwa cr ₂ Ya ₃ oxide. Da karfe oxide da aka samu ta gasa a gaban aluminum ko silicon.

game da 15 ton miliyan na chromite tama da aka samar a 2000 shekara, wanda aka sarrafa a cikin 4 ton miliyan na ferrochrome, 70% kunshi chromium-baƙin ƙarfe gami, da kiyasta kasuwar darajar da aka $ 2.5 biliyan.

key Features

Halayyar sinadari chromium ne saboda da cewa shi ne a mika mulki karfe karo na hudu, lokacin da na lokaci-lokaci tebur da kuma located tsakanin vanadium da manganese. Kunshe a cikin VI kungiyar. Yana narke a 1907 ° C. A gaban oxygen Chrome hanzari Forms bakin ciki Layer da oxide da kare da karfe daga m dauki tare da oxygen.

A matsayin tsaka-kashi, shi reacts da abubuwa daban-daban a rabo. Kamar wancan shi Forms mahadi tare da wani daban-daban mataki na hadawan abu da iskar shaka. Chromium - sinadari da key jihohin +2, +3 da +6, wanda 3 ne cikin barga. Bugu da kari, a rare lokuta, akwai Jihar +1, +4 +5 kuma. chromium mahadi a cikin hadawan abu da iskar shaka jihar +6 ne karfi oxidizers.

Abin da launi ne Chrome? Chemical kashi ba Anodized aluminum yaƙutu ya dafa. Kr ₂ Ya ₃ da ake amfani da karfe polishing, an kuma yi amfani da matsayin pigment kira "Chrome ganye". Ya gishiri akwai gilashi a Emerald kore. Chromium - da wani sinadari wanda gaban sa da jan yaƙutu ja. Saboda haka aka yi amfani da a samar da roba yaƙũtu.

isotopes

Isotopes da chromium atomic nauyi daga 43 zuwa 67. Yawanci, aiki sinadari kunshi uku barga siffofin: ⁵² Cr, ⁵³ Kr da kuma ⁵⁴ Cr. Daga cikin wadannan, ya fi na kowa ⁵² Kr (83,8% na dukkan halitta chromium). Bugu da kari, radioisotopes bayyana 19, na abin da ya fi barga ne ⁵⁰ Kr da rabin rayuwa mafi girma daga 1,8x10 shekaru ^17. A ⁵¹ Kr rabin-rai - 27.7 kwanaki, da kuma a cikin dukkan sauran rediyoaktif isotopes bai wuce 24 hours, kuma mafi yawansu ba su shi yana kasa da minti daya. A kashi ma yana da biyu meta.

Chromium isotopes a cikin duniya a ɓawon burodi, yawanci tare isotope na manganese, wanda aka yi amfani a fannin binciken kasa. ⁵³ Kr kafa ta rediyoaktif lalata na ⁵³ mn. A rabo daga mn / Kr isotope reinforces wasu bayanai game da farkon tarihin na hasken rana tsarin. Canje-canje a cikin rabbai ⁵³ Kr / ⁵² Kr da mn / Kr na daban-daban meteorites ya tabbatar da cewa sabon nuclei aka kafa nan da nan kafin samuwar da hasken rana tsarin.

Chemical kashi chromium: Properties, da mahadi dabara

Chromium oxide (III) Kr ₂ Ya _3, kuma aka sani da sesquioxide, shi ne daya daga cikin hudu oxide da wannan sinadari. An samu daga chromite. Fili kore yawanci ake kira "Chrome kore," a lokacin da amfani a matsayin pigment ga zanen a kan enamel da gilashi. A oxide za a iya narkar da a acid don ya samar da wani gishiri, da kuma zubi Alkali - chromites.

potassium dichromate

K ₂ Kr ₂ Ya ₇ ne mai iko oxidizing wakili da shi an fi son a matsayin hanyar for tsaftacewa glassware daga organics. A saboda wannan dalili shi ne a yi amfani da wani cikakken bayani na mayar da hankali sulfuric acid. Wani lokaci, duk da haka, ana maye gurbin da sodium dichromate, dangane da hakan solubility na karshen. Bayan haka ma, zai iya tsara da aiwatar da hadawan abu da iskar shaka hanyoyin gudanar da mahadi da mayar da primary barasa zuwa wani aldehyde sa'an nan zuwa carbon dioxide.

potassium dichromate chromium zai iya sa dermatitis. Chrome ne mai yiwuwa cikin hanyar wayar da kai ga dermatitis ci gaba, musamman ma a cikin hannãyenku da forearms, wanda shi ne na kullum, da wuya a iya warke. Kamar sauran mahadi Kr (VI), potassium dichromate carcinogenic. Dole ne a abar kulawa da safar hannu da kuma dace kariya.

chromic acid

Tamkar fili yana da tsarin H ₂ cro _4. Babu Chrome kuma acidic dichromate ba faruwa a yanayi, amma su anions da ake samu a wani iri-iri na kayan. "Chromic acid" wanda za a iya samu a sayarwa, a gaskiya shi ne wani acid anhydride - trioxide cro _3.

Gubar chromate (II)

PbCrO ₄ yana da wani haske rawaya launi da kuma a aikace yake insoluble a ruwa. Domin wannan dalili, shi ya samu aikace-aikace kamar yadda canza launi pigment, da ake kira "rawaya rawanin."

Kr da pentavalent Mu

Chrome da aka bambanta da da ikon samar da pentavalent connection. Fili halitta Kr (I) da kuma hydrocarbon m. Pentavalent bond kafa tsakanin chromium kwayoyin halitta. Its dabara za a iya rubuta kamar Ar-Kr-Kr-Ar, a cikinsa Ar wakiltar wani takamaiman aromatic kungiyar.

aikace-aikace

Chromium - sinadari wanda Properties ya bayar da dama daban-daban aikace-aikace, wasu daga wanda aka nuna a kasa.

Metals shi anka juriya ga lalata da wata m surface. Saboda haka, wani ɓangare na Chrome gami kamar bakin karfe, amfani da misali a cikin cutlery. Yana kuma amfani da ake ji da Chrome shafi.

Chromium ne mai kara kuzari ga daban-daban halayen. Saboda shi ya sa kyawon tsayuwa ga harbe-harben na tubalin. Its salts tanned fata. potassium bichromate da ake amfani da hadawan abu da iskar shaka hanyoyin gudanar da mahadi kamar alcohols da aldehydes, kazalika da tsaftacewa glassware. Yana hidima a matsayin kayyade wakili don dyeing masana'anta, kuma ana amfani da daukar hoto da kuma bugu.

Cro ₃ amfani ga samar da Magnetic kaset (misali, rikodin) cewa da mafi alhẽri halaye fiye da fina-finan tare da baƙin ƙarfe oxide.

Aikin a ilmin halitta

Trivalent chromium - da sinadaran abubuwa da ake bukata domin metabolism na sukari a cikin mutane. A bambanci, hexavalent Kr ne sosai guba.

rigakafi

Ƙarfe chromium fili Kr (III), an kullum ba a dauke su m ga kiwon lafiya, amma kayan dauke Kr (VI), zai iya zama mai guba idan ingested ko inhaled. Mai irin wannan abubuwa suna irritating ga idanu, fata da kuma mucous membranes. Tare da ci gaba da daukan hotuna na chromium mahadi (VI) na iya haifar da lalacewar da ido idan ba a bi yadda ya kamata. Bugu da kari, a gane carcinogen. A kashi na mutuwa na sinadari - game da rabin teaspoon. Bisa ga shawarwari na World Health Organization, da iyakar halatta taro na Kr (VI) a shan ruwa ne 0.05 MG da lita.

Tun da chromium mahadi aka yi amfani a dyes kuma ga Tanning fata, su sukan samu a kasar gona da ruwan karkashin kasa watsi da masana'antu da wuraren cewa bukatar muhalli cleanup da kuma dawo da. Share fage dauke Kr (VI), har yanzu yadu a yi amfani da Aerospace masana'antu da kuma masana'antu na mota.

kashi Properties

Ainihin jiki Properties na chromium ne kamar haka:

• A atomic yawan 24.
• Atomic nauyi: 51,996.
• Narkewa batu: 1890 ° C.
• Tafasar batu: 2482 ° C.
• A hadawan abu da iskar shaka Jihar +2, +3, +6.
• Electron sanyi: [Ar] 3d ⁵ 4s ^1.