Enye yeempumelelo ezinkulu kwinqanaba lezenzululwazi yayikukuhlelwa kunye nokulungelelaniswa kwezinto. Uphononongo lweempawu zemiba lubuyela emva kwixesha lezazi zesayensi, izazinzulu zale ndawo bezisoloko zikhumbula ngokubaluleka kokusekwa kwenkqubo yokuhlela, eya kuthi ivumele ulawulo olunocwangco lwezinto ezazisaziwa ngelo xesha.
Yiyo loo nto, emva kwemizamo emininzi, itafile eyaziwayo ye-electronegativities yaphuhliswa, ekwabizwa ngokuba yitheyibhile yamaxesha kaMendeleev, lolona luhlu lusebenzayo kunye nenkqubo yombutho esinayo ukuza kuthi ga ngoku. Kuyo izinto zilungelelaniswe ngaphakathi ukusebenza kwee-electronegativities, elingumlinganiselo wamandla ee-elektroni kwigobolondo lokugqibela lokudibanisa nezinye iiathom, kodwa siza kuthetha ngaloo nto.
Yintoni i-electronegativity?
Ngaphambi kokuya ngokupheleleyo kulo mbandela, kubalulekile ukucacisa ukuba yonke into yenziwe zii-atom, njengoko kuchaziwe nguJohn Dalton ngo-1803. I-athomu yiyunithi yemiba ephambili nengabonakaliyo, equlathe inucleus, ejikeleze ii-electron kunye Iiproton zijikeleza kumjikelo we-elliptical, kwaye zii-elektroni ezikhoyo kumaleko wokugqibela wento ekwimeko yokuhlangana umisela umthamo wento nganye ukwenza iikhompawundi. Yile nto ichaza i-electronegativity, amandla e-athomu okudibanisa ngokudibana nezinye iiathom.
Le nkqubo ichazwa sisenzo samanani amabini:
- Ubunzima beatom: Bungakanani ubunzima bebonke beeproton kunye nee-neutron kwi-athomu enye.
- I-Valence electron: Amasuntswana ahlawuliswe gwenxa akumanqanaba okugqibela e-athomu, enza isixa samasuntswana akhoyo ukwenza utshintsho xa kusenziwa iikhompawundi.
Ukuphuhliswa kwetafile ye-electronegativity
Ekufuneni kwabo ulwahlulo olwaneleyo lwezinto, izazinzulu ezininzi zavelisa izimvo malunga nokuba yeyiphi inkqubo efanelekileyo, enokuthi ifikeleleke kuyo izinto ngendlela elungeleleneyo, kuthathelwa ingqalelo iipropathi zazo. Oososayensi abalandelayo benze igalelo elibalulekileyo elenza igalelo kuphuhliso lwetheyibhile yangoku ye-electronegativities:
- UAntoine Lavoisier: Ucalulo olwenziwe yile nzulu-lwazi lwenziwa ngokungenasizathu, ngaphandle kokuthathela ingqalelo naziphi na iikhrayitheriya zokuhlelwa, ngenxa yoko ukuhlelwa kwakhe akuphumelelanga.
- UJohann Dobereiner: Le nzulu-lwazi yaziwa ngokuphuhlisa oothixo abanegama lakhe. Uphuhlise isifundo apho ahlela khona izinto kwiqela labathathu, efumanisa xa esenza uthelekiso lokuba izihlobo zabo zeatom (ezimiselwe ukusebenzisa ubukhulu be spectrometer), kunye namaxabiso athile ezinto zabo, babedibene. Ke ngoko, banokuxelwa kwangaphambili kusetyenziswa uqikelelo lwemathematika. Isokhemisi yaseBritane UJohn newlands, isebenze kwisiseko esenziwe ngu-Dobereiner, kwaye ke ikwazile uku-odola izinto kwitafile namaqela ezinto ezinobunzima be-atom ngokobungakanani obandayo; Ngeli qela, iBritane yafuna ukwenza itafile apho ipateni yokuphindaphindwa kwamaphepha e iipropathi zomzimba zezinto. Kuba olo phindaphindo lwaludityanisiwe malunga nezinto eziyi-8, zazichazwe ngegama lika "Umthetho wee-octaves".
- ULothar Meyer: Uyaziwa ngokwandisa ulwazi kwicandelo lokufunda ubudlelwane beepropathi zomzimba kunye neepropathi zeatom zezakhi. Umsebenzi wakhe wawuncedisa, kwaye ngokuzimeleyo, ngomsebenzi oveliswe nguMendeleev.
- UDmitri Mendeleev: Ngokusekwe kwizikhundla ze umthetho wamaxesha athileUsosayensi lo uphuhlise owona msebenzi uphumeleleyo wokwahlulahlula izinto, osasebenza (notshintsho, apho izinto ezintsha ezifunyenweyo zongezwe khona. Wazibeka ezi zinto ngokuthathela ingqalelo ubunyani bazo, kwaye wayenombono wokushiya iibhokisi apho kungekho nto fit, ngokulindela ukuba kuya kulunga into engekafunyanwa.Izinto ezaziwayo ezibalekileyo kwiiparameter zomyalelo ziye zaphawulwa ngokwahlukeneyo, endaweni yokubandakanywa ngokungenabuzwilakhe (Impazamo eyenziwe nguLavoisier kunye neNewlands). Ngokubhekisele kwi-electronegativity ngaphakathi kwetafile, umgaqo ngokubanzi ngu: I-Electronegativity lixabiso elonyukayo njengoko sisiya ngasekunene kwetafile, ukubona ukwehla xa usiya ngasekhohlo. Izinto ezingaphezulu kwetafile zinamaxabiso aphezulu e-electronegativity.
Isikali se-Electronegativity
Amaxabiso ahlukeneyo obuchwephesha bokubona uhlobo lobophelelo olwenziwe, ke, ukufundwa kwale nkqubo kwaba yinto enomdla, kwaye kwenziwa iipostulates ezimbini:
Isikali Pauling: Ngokwezifundo zikaPauling, kwafumaniseka ukuba i-electronegativity yipropathi eyahlukileyo, kuba ixhomekeke kwimeko ye-oxidation yento leyo. Ukuqwalaselwa kwakhe kwamvumela ukuba abone ukuba, ukuba kuthatyathwa, okanye umahluko, wobuchwephesha benziwe, sinokuxela kwangaphambili uhlobo lobumbano oluza kwenziwa, kuba wamisela isikali:
- Isibophelelo se-Ionic: I-Electronegativity gradient inkulu kune okanye ilingana no-1.7. Olu bhonkco luhlala luvela phakathi kwezinto zentsimbi kunye nezinto ezingezizo zesinyithi.
- Isibophelelo esidibeneyo Xa umahluko ukuluhlu lwe-1.7 ukuya ku-0.4. Kuqhelekile ukuzibona kwii-non-metallic compounds.
- Unxibelelwano lwePolar: Umahluko ulingana okanye ungaphantsi kwe-0.4.
Isikali seMulliken: Isekwe kubumbano lwe-elektroniki lwezinto, ezichaza utyekelo lwabo lokufumana intlawulo engeyiyo, yiyo loo nto ichaza ukubanakho kwento yokwamkela ii-elektroni. Ikwasebenza ngokusebenza kwe-ionic, ethi yona ichonge ubume bezinto ukuze ithathe intlawulo elungileyo (izinto ezihlawuliswe ngokuqinisekileyo zezo zinikezela ngee-elektroni kwibhola yazo yokugqibela). Eli nqanaba lisebenza ngamaxabiso aphakathi.