Qhov sib txawv tseem ceeb ntawm chromium thiab hexavalent chromium yog tias chromium yog cov khoom siv tshuaj thaum hexavalent chromium yog ib qho tshuaj uas muaj chromium hauv nws lub xeev +6 oxidation.
Chromium yog cov hlau uas muaj txiaj ntsig zoo hauv kev tsim cov alloys. Lo lus hexavalent chromium yog hais txog cov tebchaw uas muaj chromium. Cov hlau tshwm sim hauv lub xeev oxidation +6. Yog li, qhov no txhais tau hais tias cov hexavalent chromium compound muaj chromium atoms uas muaj 6 electrons tshem tawm ntawm lub sab nrauv orbitals.
Chromium yog dab tsi?
Chromium yog ib yam tshuaj muaj atomic tooj 24. Nws yog ib tug hlau uas muaj ib tug silvery metallic tsos. Tsis tas li ntawd, lub caij no yog thawj cov tshuaj lom neeg ntawm pab pawg 6 hauv lub sijhawm teem sijhawm. Peb tuaj yeem categorize nws raws li kev hloov pauv hlau; nws nyuaj tab sis nkig. Nws yog ib qho tseem ceeb raws li lub ntsiab additive rau hlau alloys xws li stainless hlau. Tsis tas li ntawd, cov yam ntxwv tseem ceeb uas ua rau nws tus nqi siab yog siab corrosion kuj thiab hardness. Qee cov tshuaj lom neeg ntawm chromium muaj raws li hauv qab no:
• Lub cim yog Cr.
• A d-block element
• Electron configuration yog [Ar]3d54s1
• Muaj nyob rau theem khoom ntawm tus qauv kub thiab siab
• Melting point yog 1907 °C
• Boiling point yog 2671 °C
• Qhov ntom yog li ntawm xya npaug tshaj qhov ntom ntawm dej
• Lub xeev oxidation feem ntau yog +3 thiab +6
• Tus neeg sawv cev muaj zog oxidizing piv rau molybdenum thiab tungsten oxides
Daim duab 01: Chrome Daj
Qee lub cev tseem ceeb muaj raws li hauv qab no:
• nyuaj heev
• tuaj yeem khawb cov qauv ntawm quartz vim qhov nyuaj siab
• Kev tiv thaiv siab rau tarnishing
• Tsis tshua muaj siab xav xav
• Antiferromagnetic xaj ntawm chav tsev kub (siab dua 38 ° C nws yog paramagnetic)
• Ua kom dhau los ntawm oxidation thaum cov hlau raug rau huab cua ib txwm
Thaum xav txog kev siv cov chromium, nws yog ib qho tseem ceeb hauv cov hlau tsis muaj steel, muaj txiaj ntsig zoo rau lub hom phiaj txheej txheej, xws li cov xim daj, chromium oxides li xim ntsuab, khaws cia ntoo (chromium +6 ntsev), thiab lwm yam.
Hexavalent Chromium yog dab tsi?
Hexavalent chromium yog txhua qhov sib xyaw uas muaj chromium hauv +6 oxidation xeev. Feem ntau, peb tau txais daim ntawv hexavalent ntawm chromium los ntawm chromium ore. Tab sis, muaj lwm cov tshuaj hexavalent ib yam nkaus, xws li chromium trioxide.
Daim duab 2: Chromium Trioxide
Tsis tas li ntawd, cov khoom sib txuas no tseem ceeb hauv kev lag luam textile li dyes, tseem ceeb rau kev txuag ntoo, raws li cov khoom hauv cov khoom tiv thaiv corrosion, cov khoom hauv cov xim, thiab lwm yam. Txawm li cas los xij, cov tshuaj hexavalent no yog tshuaj lom thiab suav tias yog tib neeg carcinogens. Nws yog vim cov qauv ntawm hexavalent chromium zoo ib yam li sulfate; Yog li, nws yooj yim thauj mus rau hauv cov hlwb ntawm cov channel sulfate.
Qhov txawv ntawm Chromium thiab Hexavalent Chromium yog dab tsi?
Chromium yog cov khoom siv tshuaj muaj atomic tooj 24. Qhov sib txawv tseem ceeb ntawm chromium thiab hexavalent chromium yog tias chromium yog cov khoom siv tshuaj thaum hexavalent chromium yog txhua qhov sib xyaw uas muaj chromium hauv nws lub xeev +6 oxidation.
Ntxiv mus, peb tuaj yeem ua cim chromium li Cr, tab sis lub cim rau hexavalent chromium yog Cr(VI) lossis chromium-6. Chromium tuaj yeem muaj nyob hauv ntau lub xeev oxidation, tab sis cov xeev ruaj khov thiab ntau tshaj yog +3 thiab +6. Tab sis, nyob rau hauv hexavalent compounds, cov chromium yog qhov tseem ceeb nyob rau hauv lub +6 oxidation xeev.
Summary – Chromium vs Hexavalent Chromium
Chromium yog cov khoom siv tshuaj muaj atomic tooj 24. Qhov sib txawv tseem ceeb ntawm chromium thiab hexavalent chromium yog tias chromium yog cov khoom siv tshuaj thaum hexavalent chromium yog txhua qhov sib xyaw uas muaj chromium hauv nws lub xeev +6 oxidation.
