Waikura chromium

He maha ngā pūhui matū arā, o rua huānga ohie - Cr ko e, - no ki te piha haapiiraa o pūhui pararopi - waikura. Ratou ingoa noa - waikura chromium, tangohia atu i roto i te 'tau Rōmana tohu te honohono, o te whakarewa. Ētahi atu ingoa me o ratou tātai matū:

• chromium (II) waikura - chromium waikura, CrO;
• chromium (III) waikura - chromic matomato, chromium sesquioxide, Cr2O3;
• chromium (IV) waikura - waikura chromium, CrO2;
• chromium (VI) waikura - chromic anhydride, chromium trioxide, CrO3.

He pūhui i roto i nei te shestivalenten whakarewa me te whai ōkai teitei o chromium. Tenei totoka, koreami, i roto i te ahua me te mea he tioata pouri-whero (i roto i te rangi, horahia e ratou i roto e tika ana ki te hygroscopic kaha). taimaha titiwha - 99.99 g / kamiriona. Kiato i 20 ° C rite ki te 2.70 g / cm³. ira whakakoero - 197 ° C, te kohua - 251 ° C. I 0 ° C i roto i te wai rewa 61,7 g / 100 i te 25 ° C - 63 g / 100 ml i 100 ° C - 67,45 g / 100 ml. Kei te memeha hoki te waikura i roto i te waikawa pungatara (chromic tenei ranunga, i whakamahia i roto i te taiwhanga mo horoi matū o rihi) me te waikawa hauota, te waihā, Ethyl Etere, waikawameha ahetiki, hauwaiwaro. I 450 ° decomposes C ki Cr2O3.

whakamahia chromium (VI) waikura e i roto i te tukanga o te iahiko (mo chromium parakore) mō te chromating hua konutea, whakakikorua -hiko, rite te kaihoko oxidizing kaha (mo te hanga o te poropango, isatin). Kei te whakamahia Higher waikura chromium mō te kimi waipiro i roto i te rangi whakangā. Ko te puta tauhohenga rite ki te kaupapa: 4CrO3 + 6H2SO4 + 3C2H5OH → 2Cr2 (SO4) 3 + 3CH3COOH + 9H2O. Ko te aroaro o te waipiro tohu te huringa tae otinga (tahuri matomato).

Chromium (VI) waikura, me te hexavalent katoa Kr, ko te paihana puai (horopeta whakamate - 0.1 g). No te mea o tona mahi nui CrO3 ai pātīmata (ki pahūtanga) matū organic , i roto i te whakapā ki a ratou. Ahakoa te pähekeheke iti, he mōrearea te teitei te waikura chromium ki te hau, he mate pukupuku pūkahukahu rite. Ki runga ki te whakapā atu ki te kiri (ara, ki te te nekehia atu te reira tata) ai ritenga, dermatitis, katoatia, e whakaoho ana i te whanaketanga o te mate pukupuku.

Tetravalent waikura chromium ki CrO2 ahua ko te mārō i roto i te puka o te mangu tioata tetrahedral ferromagnetic. Chromium waikura he papatipu titiwha o 4 83.9949 g / mol, kiato 4,89 g / cm³. Ko te taonga e rewa ana te wā kotahi decomposing, i te pāmahana o te 375 ° C. E kore e te wai memeha. whakamahia te reira i roto i pāpāho tuhi autō rite te taonga mahi. Ki te rongonui o te CD-ROM, me te puku DVD-ROM ki te whakamahi i chromium (IV) te heke haere waikura. I synthesized tuatahi te reira i roto i te 1956 e te kēmihi i Ei Dupont kamupene Norman L. Cox i whāwehe o trioxide chromium i te aroaro o te wai i te pāmahana o te 640 ° C, me te pēhanga o 200 MPa. E ai ki te raihana Dupont whakaputaina e Sony i Tapone me BASF i Germany.

3 chromium waikura Cr2O3 ko te rauemi pai-baked totoka i te marama ki te matomato pouri. ōrite papatipu titiwha 151,99 g / mol. Kiato - 5.22 g / cm³. ira whakakoero - 2435 ° C, kohua - 4000 ° C. Ko te taupū hakoko o te taonga parakore - 2.551. e kore he wairewa i te wai, te waipiro, hauwaiwaro, waikawa tenei waikura. Ka rite ki whakatata reira te kiato o te corundum kiato, e faaterehia te reira i roto i formulations te oro āpiha (hei tauira, whakapiri gọi). Tenei Ko tetahi o nga waikura taketake o chromium, whakamahia nei te rite te ngarahu. Hoki te wā tuatahi i runga i te hangarau ngaro i riro te reira i roto i 1838 i roto i te puka o te puka hydrated mārama. I roto i te natura, i kitea i roto i te puka o te Konqueror rino ore FeO • Cr2O3.

waikura Divalent chromium - totoka tae pango whero ranei ki te ira whakakoero o 1550 ° C. Rewa ki whāwehe. taimaha titiwha - 67,996 g / mol. e kore te mea pyrophoric chromium waikura (II) o te tae whero, me te taonga ano ko te pyrophoric pango. tahuna ana Paura māhorahora i roto i te rangi, kia taea te rongoa reira anake i raro i te apa o te wai, rite kore e te reira taunekeneke ki reira. Ko te tino uaua waikura Black o chromium ki te whiwhi i roto i te puka parakore.

Hoki chromium waikura ki honohono raro āhuatanga taketake angamaheni, a mo te ōkai ki te honohono, teitei - waikawa.