I-Molybdenum

Izakhiwo ze-Molybdenum

Inombolo ye-athomu 42
Inombolo ye-CAS 7439-98-7
Isisindo se-athomu 95.94
Iphoyinti lokuncibilika 2620°C
Iphuzu elibilayo 5560°C
Ivolumu ye-athomu 0.0153 nm3
Ukuminyana ku-20 °C 10.2g/cm³
Isakhiwo sekristalu cubic egxile emzimbeni
I-lattice engaguquki 0.3147 [nm]
Ukuchichima koqweqwe lomhlaba 1.2 [g/t]
Isivinini somsindo 5400 m/s (at rt)(induku ezacile)
Ukunwetshwa kwe-thermal 4.8 µm/(m·K) (ku-25 °C)
I-Thermal conductivity 138 W/(m·K)
Ukumelana nogesi 53.4 nΩ·m (ku-20 °C)
Mohs ubulukhuni 5.5
Vickers ubulukhuni 1400-2740Mpa
Ukuqina kweBrinell 1370-2500Mpa

I-Molybdenum iyikhemikhali enophawu luka-Mo kanye nenombolo ye-athomu engu-42. Igama lisuselwa ku-Neo-Latin molybdaenum, lisuselwa ku-Ancient Greek Μόλυβδος molybdos, okusho umthofu, njengoba ama-ore ayo adidaniswa nensimbi yomthofu.Amaminerali e-molybdenum ayaziwa kuwo wonke umlando, kodwa i-elementi yatholakala (ngomqondo wokuyihlukanisa njengenhlangano entsha kusawoti wamaminerali wezinye izinsimbi) ngo-1778 ngu-Carl Wilhelm Scheele.Insimbi yaqala ukuhlukaniswa ngo-1781 nguPeter Jacob Hjelm.

I-Molybdenum ayenzeki ngokwemvelo njengensimbi yamahhala Emhlabeni;itholakala kuphela ezindaweni ezihlukahlukene ze-oxidation kumaminerali.I-elementi yamahhala, insimbi esiliva ene-grey cast, inephuzu lokuncibilika lesithupha eliphakeme kunawo wonke lanoma iyiphi i-elementi.Yakha kalula ama-carbides aqinile, azinzile kuma-alloys, futhi ngenxa yalesi sizathu iningi lokukhiqizwa komhlaba wonke (cishe ama-80%) lisetshenziswa kuma-alloys ensimbi, okuhlanganisa ama-alloys aphezulu kanye nama-superalloys.

I-Molybdenum

Izingxube eziningi ze-molybdenum zinokuncibilika okuphansi emanzini, kodwa uma amaminerali ane-molybdenum ethinta umoya-mpilo namanzi, i-ion ye-molybdate MoO2-4 ewumphumela iyancibilika impela.Ngokwezimboni, ama-molybdenum compounds (cishe amaphesenti angu-14 okukhiqizwa komhlaba we-elementi) asetshenziswa ekusetshenzisweni kwengcindezi ephezulu kanye nezinga lokushisa eliphezulu njengama-pigments nama-catalysts.

Ama-enzyme aphethe i-molybdenum ayizisusa zamagciwane ezivame kakhulu ekuphuleni isibopho samakhemikhali ku-nitrogen yamangqamuzana asemkhathini ngesikhathi sokulungiswa kwe-nitrogen yebhayoloji.Okungenani ama-enzyme e-molybdenum angama-50 manje ayaziwa kubhaktheriya, izitshalo, nezilwane, nakuba ama-enzyme e-bacterial kanye ne-cyanobacterial kuphela abandakanyeka ekulungiseni i-nitrogen.Lawa ma-nitrogenases aqukethe i-molybdenum esesimweni esihlukile kwamanye ama-enzyme e-molybdenum, wonke aqukethe i-molybdenum ene-oxidized ngokugcwele ku-molybdenum cofactor.Lawa ma-enzyme ahlukahlukene e-molybdenum cofactor abalulekile ezintweni eziphilayo, futhi i-molybdenum iyingxenye ebalulekile yokuphila kuzo zonke izinto eziphilayo eziphakeme ze-eukaryote, nakuba ingekho kuwo wonke amagciwane.

Izici ezingokomzimba

Ngendlela yayo emsulwa, i-molybdenum iyinsimbi e-silvery-grey enobunzima be-Mohs obungu-5.5, kanye nesisindo se-athomu esijwayelekile esingu-95.95 g/mol.Inephuzu lokuncibilika elingu-2,623 °C (4,753 °F);kwezakhi ezenzeka ngokwemvelo, i-tantalum, i-osmium, i-rhenium, i-tungsten, ne-carbon kuphela enamaphuzu aphezulu okuncibilika.Inelinye lama-coefficients aphansi kakhulu okwanda okushisayo phakathi kwezinsimbi ezisetshenziswa ukuthengisa.Amandla aqinile wezintambo ze-molybdenum akhuphuka cishe izikhathi ezi-3, kusukela cishe ku-10 kuya ku-30 ​​GPa, lapho ububanzi bawo buncipha ukusuka ku-~50-100 nm kuya ku-10 nm.

Izakhiwo zamakhemikhali

I-Molybdenum iyinsimbi yoguquko ene-electronegativity engu-2.16 esikalini sika-Pauling.Akubonakali kusabela ngomoya komoya-mpilo noma amanzi ezingeni lokushisa legumbi.I-oxidation ebuthakathaka ye-molybdenum iqala ku-300 °C (572 °F);i-oxidation ngobuningi kwenzeka emazingeni okushisa angaphezu kuka-600 °C, okuholela ku-molybdenum trioxide.Njengezinsimbi eziningi ezisindayo zoguquko, i-molybdenum ikhombisa ukuthambekela okuncane ukwenza i-cation kusisombululo esinamanzi, nakuba i-Mo3+ cation yaziwa ngaphansi kwezimo ezilawulwa ngokucophelela.

Imikhiqizo Eshisayo ye-Molybdenum