Imithetho Eyisisekelo Yekhemistri: Izisekelo Eziqhuba Ikhemistri Yesimanje
I-Pendahuluan
I-Chemistry iyigatsha lesayensi yemvelo elifunda ukwakheka, isakhiwo, izakhiwo, kanye noshintsho lwezinto. Ngemuva komlingo wokusabela kwamakhemikhali okunquma izakhiwo kanye noshintsho lwezinto kukhona izimiso eziyisisekelo ezaziwa ngokuthi imithetho eyisisekelo ye-chemistry. Le mithetho ayigcini nje ngokwakha isisekelo solwazi lwamakhemikhali kodwa futhi idlala indima ebalulekile ekuthuthukisweni kwesayensi nobuchwepheshe. Kulesi sihloko, sizohlola eminye yemithetho eyisisekelo ye-chemistry eye yaqondisa impucuko yabantu ekuqondeni okujulile umhlaba ozungezile.
1. Umthetho Wokulondolozwa Kwenqwaba
UMthetho Wokulondolozwa Kwe-Mass, owaziwa nangokuthi uMthetho kaLavoisier, uqanjwe ngo-Antoine Lavoisier, owawusungula ngekhulu le-18. Lo mthetho uthi isisindo sento ohlelweni oluvaliwe sihlala singaguquguquki, kungakhathaliseki ukuthi hlobo luni loshintsho lwamakhemikhali oluvelayo. Ngamanye amazwi, isisindo esiphelele sama-reactants ekusabeleni kwamakhemikhali silingana nesisindo esiphelele semikhiqizo ekhiqizwayo.
Isibonelo esilula salo mthetho singabonakala ekusabeleni komlilo kwekhandlela. Nakuba i-wax ibonakala incipha kakhulu njengoba isha, isisindo semikhiqizo yomlilo (i-carbon dioxide kanye nomhwamuko wamanzi) uma silinganiswa ngokunembile sizolingana nesisindo se-wax kanye nomoya-mpilo osabelayo.
UMthetho Wokulondolozwa Kwesisindo udala isisekelo sokuhlaziywa kwenani ekuphenduleni kwamakhemikhali futhi uvumela ososayensi ukuthi babhale izibalo zamakhemikhali ezilinganisiwe.
2. Umthetho Wezilinganiso Ezihlala Njalo (Umthetho kaProust)
Isazi samakhemikhali saseFrance uJoseph Proust ngasekupheleni kwekhulu le-18 wasungula uMthetho Wezilinganiso Eziqondile, othi inhlanganisela ethile yamakhemikhali ihlala iqukethe izakhi zayo eziyingxenye ngesilinganiso esifanayo sobuningi, kungakhathaliseki ukuthi zivelaphi noma indlela yokwakheka kwazo.
Isibonelo, i-molecule yamanzi (H₂O) kungakhathaliseki ukuthi ivelaphi—kungakhathaliseki ukuthi ivela emvuleni, echibini, noma kunoma yimuphi omunye umthombo—ihlala iqukethe ama-athomu amabili e-hydrogen kanye ne-athomu elilodwa le-oxygen ngesilinganiso esinqunyiwe sesisindo (cishe i-1:8).
Lo mthetho ubaluleke kakhulu ekuthuthukisweni kwamafomula amakhemikhali ahambisanayo futhi uyisisekelo sokuhlola ubumsulwa bamakhemikhali amakhemikhali.
3. Umthetho Wezilinganiso Eziningi
UJohn Dalton, usosayensi waseNgilandi owaziwa ngemfundiso yakhe ye-athomu, wethula uMthetho Wezilinganiso Eziningi ekuqaleni kwekhulu le-19. Lo mthetho uthi, uma izakhi ezimbili zingakha inhlanganisela engaphezu kweyodwa, ubuningi besakhi esisodwa obuhlanganiswe nesisindo esiqinile sesinye isakhi buzoba ngezilinganiso ezilula zenombolo ephelele.
Isibonelo, ikhabhoni nomoya-mpilo kungakha ama-compound amabili ahlukene: i-carbon monoxide (CO) kanye ne-carbon dioxide (CO₂). Ku-CO₂, isilinganiso sobuningi bekhabhoni nomoya-mpilo singu-12:16 (noma 3:4), kuyilapho ku-CO₂, isilinganiso sobuningi bekhabhoni nomoya-mpilo singu-12:32 (noma 3:8). Lesi silinganiso (4:8 noma 1:2) siyisibonelo esiphelele sezilinganiso eziningi.
UMthetho Wezilinganiso Eziningi waqinisa umqondo wama-athomu futhi wethula umqondo wokuthi ama-athomu ayizingxenye ezincane kakhulu zezinto ezihlanganyela ekusabeleni kwamakhemikhali.
4. Umthetho Wegesi Ofanele (Umthetho ka-Avogadro)
U-Amedeo Avogadro, usosayensi wase-Italy, waphakamisa umbono wokuthi, ekushiseni okufanayo nasekucindezelweni, amavolumu alinganayo amagesi aqukethe inani elifanayo lama-molecule. Lo mbono, owaziwa ngokuthi uMthetho ka-Avogadro, wadlala indima ebalulekile ekuthuthukisweni kwethiyori yegesi efanele kanye ne-thermodynamics.
Ngokwezibalo, lo mthetho ungachazwa ngokuthi i-PV = nRT, lapho:
– P ingcindezi yegesi,
– V yivolumu yegesi,
– n yinani lama-moles egesi,
– R iyi-gesi engaguquki yonke, futhi
– T yizinga lokushisa ku-Kelvin.
Sisebenzisa uMthetho ka-Avogadro, singaqonda ukuthi amagesi aziphatha kanjani ngaphansi kwezimo ezahlukene futhi sibikezele izinguquko kumagesi ngokusekelwe ekushiseni, ingcindezi, kanye nomthamo.
5. Umthetho Wokulingana Kwamakhemikhali (Umthetho kaLe Chatelier)
Umthetho kaLe Chatelier, oqanjwe ngoHenri Louis Le Chatelier, uthi uma uhlelo lokulinganisela kwamakhemikhali lubhekana noshintsho ezimweni (ukuhlushwa, ingcindezi, izinga lokushisa), uhlelo luzosabela ngokushintsha ukulinganisela luye ohlangothini olunciphisa ushintsho.
Isibonelo sangempela singabonakala embonini yamakhemikhali, njengokukhiqizwa kwe-ammonia (NH₃) ngenqubo ye-Haber. Ukwandisa ingcindezi kushintsha ukulingana kuya ekwakhekeni kwe-ammonia eyengeziwe, ngokuvumelana nesimiso sikaLe Chatelier.
Lo mthetho ubaluleke kakhulu ekulawuleni ukusabela kwamakhemikhali ezimbonini ukuze kwandiswe umkhiqizo ofiselekayo.
Isiphetho
Imithetho eyisisekelo yekhemistri iyizisekelo ezisisiza ukuqonda nokubikezela ukusabela kanye nezakhiwo zezinto. UMthetho Wokulondolozwa Kwesisindo usifundisa ngokungaguquguquki kwesisindo ekuphenduleni kwamakhemikhali, UMthetho Wezilinganiso Eziqondile uqinisekisa ukuvumelana kwamafomula ahlanganisiwe, UMthetho Wezilinganiso Eziningi ufakazela isakhiwo se-athomu samakhemikhali, UMthetho ka-Avogadro uchaza ukuziphatha kwamagesi, kanye noMthetho kaLe Chatelier unikeza ukuqonda nge-dynamics yokulingana kwamakhemikhali.
Ukuqonda okujulile ngale mithetho akugcini nje ngokwenza kube lula kososayensi nonjiniyela ukudala ubuchwepheshe obusha, kodwa futhi kusenza sikwazi ukwazisa nokuqonda kangcono umhlaba omncane obumba izimpilo zethu zansuku zonke. Lokhu kuqonda okuyisisekelo kunikeza ibhuloho eliya ekusungulweni nasekutholakaleni kwezinto ezintsha, okusheshisa intuthuko yesayensi nobuchwepheshe, futhi ekugcineni, impucuko yabantu.
