Uhlelo lwezikhathi: ukuhlukaniswa kwezakhi zamakhemikhali

Engxenyeni yokuqala yekhulu le-19, kwenziwa imizamo ehlukahlukene yokwenza izinto zihlelwe futhi zihlanganise izinsimbi ohlelweni lwezikhathi. Kule nkathi yomlando ukuthi uphenyo luvela, njengokuhlaziywa kwamakhemikhali.

Kusukela emlandweni wokutholakala kwetafula lezinkathi zesikhathi

Esebenzisa indlela efanayo yokunquma izindawo ezithile zamakhemikhali, ososayensi bangaleso sikhathi bazama ukuhlanganisa ndawonye izakhi ngokusekelwe kwezici zabo zokulinganisa, kanye nesisindo se-athomu.

Ukusetshenziswa kwesisindo se-athomu

Ngakho-ke, i-IV Dubereiner ngo-1817 inqume ukuthi ku-strontium isisindo se-athomu sifana nama-indices afanayo we-barium ne-calcium. Wakwazi futhi ukuthola ukuthi kunezinto eziningi ezifanayo phakathi kwezakhiwo ze-barium, i-strontium ne-calcium. Ngokusekelwe kulokhu okuqaphele, isazi samakhemikhali esidumile sakha okuthiwa i-triad yezinto. Emaqenjini afanayo, ezinye izinto zahlanganiswa:

• Sulfur, selenium, tellurium;
• I-chlorine, i-bromine, i-iodine;
• Ithimu, i-sodium, i-potassium.

Ukumiswa ngamakhemikhali

UL. Gmelin ngo-1843 uhlongoze itafula lapho abeka khona okufanayo emakhemikhali asezindaweni ezihlelekile. I-nitrojeni, i-hydrogen, i-oksijeni, yayibheka izakhi eziyinhloko, ikhiphemikhali eyinikezwe ngaphandle kwetafula lakhe.

Ngaphansi kwe-oksijeni, i-tetrads yahlelwa (izimpawu ezingu-4 ngasinye) kanye nama-pentade (izinhlamvu ezingu-5 ngasinye). Amakhombi etafuleni lamaphesenti afakwa kwigama elithi Berzelius. Ngokusho kohlelo lukaGmelin, zonke izici zakhiwe ngokunciphisa ukukhethwa kwezikhundla zendawo ngaphakathi kwesigcawu ngasinye se-periodic system.

Hlanganisa izingxenye ngokuqondile

U-Alexander Emil de Chancourtua ngo-1863 zonke izici zafakwa ekukhuphukeni izilinganiso ze-athomu ku-cylinder, zihlukanisa zibe izingqimba eziningana. Ngenxa yalesi sigaba ku-verticals, izakhi ezinezindawo ezifanayo zomzimba nezamakhemikhali zitholakala.

Umthetho we-octaves

D. IziNewlands ezitholwa ngo-1864 iphethini elithakazelisayo. Ngokuhlelwa kwezakhi zamakhemikhali ekwenzeni izisindo ze-athomu ezinyukayo, isici ngasinye sesishiyagalombili sibonisa ukufana kokuqala. Iqiniso elifanayo eNewlands elibizwa ngokuthi umthetho octaves (amanothi ayisishiyagalombili).

Isistimu yakhe yezinsuku ngezikhathi yayinemibandela kakhulu, ngakho umqondo wososayensi owaziwayo waqala ukubizwa ngokuthi "octave" version, ukuyihlanganisa nomculo. Kwakuyihlukahluka kweNewlands eyayiseduze nesakhiwo samanje se-PS. Kodwa ngokusho komthetho we-octave ongenhla, izakhi ezingu-17 kuphela ezigcinwe izakhiwo zazo zesikhathi, kanti izimpawu ezisele azibonanga njalo.

Amatafula e-Odling

I-U. Odling inikeze izihlukahluka eziningana zamatafula esakhi ngesikhathi esisodwa. Ngenguqulo yokuqala, eyadalwa ngo-1857, wahlongoza ukuwahlukanisa ngamaqembu angu-9. Ngo-1861, isazi samakhemikhali senza ezinye izilungiso ekuguqulweni kwasekuqaleni kwetafula, kuhlanganiswa ngamaqembu izimpawu eziphethe amakhemikhali afanayo.

Ithebula eline-Odling, elihlongozwayo ngo-1868, lenze uhlelo lwezinhlaka ezingu-45 ekwenzeni izinsimbi ze-athomu. Ngendlela, yilo leli tafula okwathi ngokuhamba kwesikhathi laba yisibonelo se-system periodic system ka-DI Mendeleyev.

Isigaba nge-valence

UL. Meyer ngo-1864 uhlongoze itafula, elibandakanya izici ezingu-44. Babekwe emakholomu angu-6, ngokusho kwe-valence ye-valgen. Etafuleni kwakukhona izingxenye ezimbili kuphela. Iqembu eliyinhloko lalinamaqembu ayisithupha, kuhlanganise nezimpawu ezingu-28 zokukhula kwe-athomu. Esikhathini saso isakhiwo se-pentads kanye ne-tetrads esivela ezibonakalweni zamakhemikhali ezifana nezakhiwo zamakhemikhali zibukwa. Zonke ezinye izakhi uMeyer ezifakwe etafuleni lesibili.

Umnikelo ka-DI Mendeleyev ekwakheni itafula lezici

Uhlelo lwesimiso samanje lwezikhathi zezinto zika-DI Mendeleyev lwavela ngesisekelo samatafula kaMeya, owahlanganiswa ngo-1869. Esikhathini sesibili sesibili, uMeya uhlele izibonakaliso zamaqembu angu-16, wabeka izakhi nge-pentads ne-tetrads, enikezwa ngamakhemikhali aziwayo. Esikhundleni se-valence, wasebenzisa inombolo elula yamaqembu. Kwakungekho boron, thorium, hydrogen, niobium, uranium kuwo.

Isakhiwo se-system periodic ngesimo esinikezwe ezikhathini zanamuhla aziveli ngokushesha. Kunezinyathelo ezintathu eziyinhloko lapho kusetshenzwa khona uhlelo lwezikhathi:

1. Inguqulo yokuqala yetafula yanikezwa emabhuloki wokwakha. Uhlamvu lwezikhathi zobuhlobo phakathi kwezakhiwo zezinto kanye nezindinganiso zezintambo zabo ze-athomu zalandelwa. Le nguqulo yokuhlelwa kwezibonakaliso zeMendeleev iphakanyisiwe ngo-1868-1869.
2. Usosayensi wenqaba isimiso sokuqala, ngoba asizange sibonise indlela izakhi ezaziyowela ngayo kukholomu ethile. Uphakamisa ukubeka izimpawu ngokufana kwezakhiwo zamakhemikhali (February 1869)
3. Ngo-1870, uDmitry Mendeleev wethulwa emhlabeni wesayense ohlelweni lwamanje lwezikhathi.

I-version ye- chemist yaseRussia yacubungula kokubili isimo sezinsimbi kwisistimu yezinkathi ezithile, kanye nezici zezindawo ezingekho emthethweni. Kule minyaka edlulile kusukela ekuqaleni kohlelo lwezinto ezihlakaniphile ezenziwe nguMendeleyev, ithebula alizange lenze izinguquko ezinkulu. Futhi kulezo zindawo ezasala zingenalutho ngesikhathi sikaDmitry Ivanovich, kwavela izakhi ezintsha ezatholakala ngemva kokufa kwakhe.

Izici zetafula lezinsuku

Kungani kubhekwa ukuthi uhlelo oluchazwe luyisikhathi? Lokhu kuchazwa yizimpawu ezibonakalayo zesakhiwo setafula.

Ingqikithi, iqukethe amaqembu angu-8, futhi ngayinye inezinkampani ezimbili eziyinhloko: eyinhloko (eyinhloko) neyesibili. Kuvela ukuthi wonke ama-subgroups 16. Atholakala ngokuqondile, okungukuthi, kusukela phezulu kuya phansi.

Ngaphezu kwalokho, kunemigqa enezingqimba etafuleni, ebizwa ngokuthi izinkathi. Baphinde babe nesigaba sabo esengeziwe sibe sincane nezinkulu. Ukufaniswa kwesistimu yesikhashana kuhilela ukucabangela indawo yento: iqoqo, iqoqo kanye nesikhathi salo.

Ukuthi izindawo zishintsha kanjani ezingxenyeni eziyinhloko

Zonke izingxenyana ezisemqoka etafuleni lezinsuku ziqala ngezici zenkathi yesibili. Ukuze uthole izimpawu zengxenye eyodwa eyinhloko, inani lama-electrons angaphandle lifanayo, kodwa ibanga phakathi kwama-electrons wokugcina ne-nucleus enhle ishintsha.

Ngaphezu kwalokho, ukwanda kwesisindo se-athomu (ubukhulu be-atomic) esakhiweni livela phezulu. Yile nkhomba iyisici esinqumayo ekunqumeni iphethini lokuguqulwa kwezakhiwo ngaphakathi kwezingqikithi eziyinhloko.

Njengoba irejista (ibanga eliphakathi kwe-nucleus elihle nama-electrons angaphandle angenayo) ekhulwini eliyinhloko liyakhula, izakhiwo ezingenakulinganiswa (ikhono lokuthola ama-electron ngesikhathi sokuguqulwa kwamakhemikhali) wehla. Ngokuqondene nokuguquka kwezakhiwo ze-metallic (ukubuyiswa kwama-electron kuya kwamanye ama-athomu), kuzokhula.

Ukusebenzisa uhlelo lwezikhathi, umuntu angaqhathanisa izindawo zabameleli abahlukene beqembu elilodwa eliyinhloko. Ngesikhathi uMendeleev edala uhlelo lwezikhathi, kwakungekho nolwazi ngesakhiwo sendaba. Kuyathakazelisa ukuthi ngemuva kokuba inkolelo yesakhiwo se-athomu, eye yafundwa ezikoleni zemfundo kanye neyunivesithi yamaphrofayli yamaphrofayli, manje isiqinisekisile, iqinisekisile ukucabanga kweMendeleyev, futhi ayizange iphikise imibono yakhe mayelana nokuhlelwa kwama-athomu ngaphakathi kwetafula.

I-electronegativity ezingxenyeni eziyinhloko kuya phansi iyancipha, okungukuthi, isici esingaphansi seqembu, lapho ikhono layo lokunamathisela i-athomu lizoba lincane.

Shintsha ezakhiweni zama-athomu kuma-subgroups

Njengoba isistimu ye-Mendeleev ihlala njalo, ukuguqulwa kwezakhiwo kulezi zingxenye ezincane kwenzeka ngokulandelana okulandelanayo. Amaconsi anjalo afaka izakhi eziqala esikhathini sesine (abamele imindeni kanye nemindeni). Ngezansi kulezi zingxenyana izakhiwo zensimbi ziyancipha, kodwa inani lama-electron angaphandle lifanayo kubo bonke abameleli beqembu elilodwa.

Okuyingqayizivele kwesakhiwo sesikhathi ku-PS

Isikhathi ngasinye esisha, ngaphandle kweyokuqala, etafuleni lomkhakha wezemithi waseRussia uqala ngensimbi esebenzayo yama-alkali. Ngaphezu kwalokho, izinsimbi zamamphoteric zikhonjiswa , zibonisa izindawo ezimbili eziguquguqukayo zamakhemikhali. Khona-ke kukhona izakhi eziningana ezinezici ezingezona zensimbi. Isikhathi siphelela ngegesi le-inert (elingelona lensimbi, elisebenzayo, elingabonisi imisebenzi yamakhemikhali).

Njengoba kunikezwe ukuthi uhlelo luyisikhathi, ngezikhathi kukhona ushintsho kumsebenzi. Ukusuka kwesobunxele kuya kwesokudla, ukunciphisa umsebenzi (izakhiwo zensimbi) kuzokwehla, umsebenzi we-oxidative (izakhiwo ezingezona zensimbi) ziyokhula. Ngakho-ke, izinsimbi eziqhakazile kule nkathi zingakwesobunxele, futhi okungezona izinsimbi ngakwesokudla.

Ezinkathini ezinkulu, eziqukethe imigqa emibili (4-7), umlingiswa we-periodical uvela futhi, kodwa ngenxa yobuningi babamele umndeni noma umndeni, izakhi zensimbi zochungechunge zikhulu kakhulu.

Amagama ezinkampani ezincane eziyinhloko

Ingxenye yamaqembu ezakhi ezitholakalayo kuthebula lezinsuku zinegama layo. Abamele iqembu lokuqala Amaqembu aphansi abizwa ngokuthi yi-alkali metal. Ebizweni elifanayo, izitshalo kufanele zenze umsebenzi wazo emanzini, okuholela ekusungulweni kwe-alkalis caustic.

Iqembu lesibili A libhekwa njengengxenye encane yamatshe alkali komhlaba. Lapho uxhumana namanzi, izinsimbi ezinjalo zakha ama-oxide, ayekade ebizwa ngokuthi amazwe. Kusukela ngaleso sikhathi ukuthi igama linikezwe abameleli bale nkambu.

Ama-non-metal we-subgroup abizwa ngokuthi ama-chalcogenes, futhi amaqembu angu-7A abizwa ngokuthi ama-halogen. I-subgroup yayibizwa ngokuthi i-inert gases ngenxa yomsebenzi wayo wamakhemikhali omncane.

PS ngonyaka wesikole

Kuzingane zesikole, ukuhlukahluka kwetafula lezinsuku ezivame ukuhlongozwa, lapho, ngaphezu kwamaqembu, amaqembu angaphansi, izinkathi, amafomula amakhemikhali aphezulu aphezulu kanye ne-oxide ephakeme nawo kuboniswa. Lolu hlobo lobuqili luvumela abafundi ukuba bakhe amakhono ekwakheni ama-oxide aphezulu. Kwanele ukufaka esikhundleni sento ngesibonakaliso sommeleli weqembu ukuze uthole i- oxide ephakeme ephelile .

Uma ubheka ngokubheka umbono ovamile wezihlanganisi ze-hydrogen ezinamandla, kubonakala ukuthi ziyisici kuphela sezinto ezingezansi. Emaqenjini angu-1-3 kukhona ama-dashes, njengoba abameleli bala maqembu bezinsimbi.

Ngaphezu kwalokho, kwezinye izincwadi zesikole zamakhemikhali, isibonakaliso ngasinye siboniswa uhlelo lokusabalalisa ama-electron phezu kwamazinga kagesi. Lolu lwazi alukho phakathi nomsebenzi kaMendeleev, lawo maqiniso esayense avele kamuva.

Ungabona amafomula wezinga langaphandle le-elekthronikhi, lapho kulula ukuqagela ukuthi yimuphi umndeni le nto ingokwakho. Amazwi anjalo awawamukeli ezikhathini zokuhlola, ngakho-ke, iziqu zamabanga ase-9 no-11 abaye banquma ukubonisa ulwazi lwabo lwamakhemikhali ku-OGE noma e-EGE banikeza amachashazi amnyama namhlophe ajwayelekile amatafula angama-periodic okungekho ulwazi olwengeziwe mayelana nesakhiwo se-athomu, amafomula e-oxides aphezulu, ukuhlanganiswa kwe-hydrogen ehlanganisiwe .

Isinqumo esinjalo sinengqiqo futhi siyaqondakala, ngoba kulabo bafundi abaye banquma ukulandela izinyathelo zikaMendeleev noLomonosov, ngeke kube nzima ukusebenzisa inguqulo ye-classic yesistimu, abakudingi amacebo.

Kwakuwumthetho we-periodic kanye nesistimu ye-DI Mendeleev eyadlala indima ebalulekile ekuthuthukiseni phambili kwe-theory-molecular theory. Ngemva kokudalwa kwalesi simiso, ososayensi baqala ukukhokha ngokucophelela ukutadisha kokubunjwa kwesici. Ithebula lisize kucacise ngolunye ulwazi mayelana nezinto ezilula, kanye nemvelo nezakhiwo zezinto ezakhiwa.

U-Mendeleyev ngokwakhe ucabanga ukuthi izakhi ezintsha zizovula, futhi zinikeze isikhundla sezinsimbi ohlelweni lwezikhathi. Kwakungemva kokubonakala kwalesi sikhathi sokugcina ukuthi inkathi entsha yaqala ekhemistry. Ngaphezu kwalokho, kwaqala isisekelo esiyinkimbinkimbi ekwakheni inqwaba yezesayensi ezihlobene ezihlobene nesakhiwo se-athomu nokuguqulwa kwezakhi.