I-Chemistry yisayensi efunda izakhiwo, ukwakheka, kanye noshintsho lwezinto. Njengesayensi eyisisekelo empilweni yansuku zonke, i-chemistry inemithetho eminingana eyisisekelo esebenza njengesisekelo esiyinhloko sokuqonda izinto kanye nokusabela kwazo. Lesi sihloko sizobuyekeza imithetho emine eyisisekelo ye-chemistry: Umthetho Wokulondolozwa Kwesisindo, Umthetho Wezilinganiso Eziqondile, Umthetho Wezilinganiso Eziningi, kanye Nomthetho KaGay-Lussac.
1. Umthetho Wokulondolozwa Kwenqwaba
UMthetho Wokulondolozwa Kwe-Mass, owaqala ukwethulwa ngu-Antoine Lavoisier ngo-1789, uthi isisindo esiphelele sento ngaphambi nangemva kokusabela kwamakhemikhali siyafana. Ngamanye amazwi, isisindo asinakudalwa noma sibhujiswe ekusabela kwamakhemikhali. Lesi simiso sibalulekile ekubaleni i-stoichiometry yokusabela kwamakhemikhali.
Isibonelo:
Ake sithi sinokusabela okulula kwamakhemikhali:
\[ 2H_2 + O_2 \kwesokudla 2H_2O \]
Uma siqala ngamagremu angu-4 e-hydrogen (H₂) kanye namagremu angu-32 e-oxygen (O₂), khona-ke isisindo esiphelele sezinto ngaphambi kokusabela singamagremu angu-36. Ngemva kokusabela, sizoba namagremu angu-36 amanzi (H₂O), okubonisa ukuthi isisindo esiphelele sihlala sifana.
Lo mthetho usifundisa ukuthi kuyo yonke i-chemical reaction, ubuningi be-reactants kanye nemikhiqizo kumele bulingane. Ngakho-ke, lapho sidala i-chemical equation, kumele siqinisekise ukuthi i-equation iyalingana.
2. Umthetho Wezilinganiso Ezihlala Njalo
UMthetho Wezilinganiso Eziqondile, noma uMthetho kaProust, uqanjwe ngegama lomtholi wawo, uJoseph Proust, owawuphakamisa ngo-1797. Uthi inhlanganisela yamakhemikhali ihlala yakhiwa yizinto ezifanayo ngesilinganiso sobuningi obuhleliwe. Lokhu kusho ukuthi noma yiliphi isampula lamanzi (H₂O), isibonelo, lihlala liqukethe i-hydrogen ne-oxygen ngesilinganiso sobuningi esifanayo, cishe u-1:8.
Isibonelo:
Uma sithatha amanzi kunoma yimuphi umthombo, sizothola ukuthi isilinganiso sobuningi be-hydrogen nomoya-mpilo sihlala singu-1:8. Lokhu kusebenza emanzini avela olwandle, emachibini, noma emanzini emvula.
Lo mthetho ubalulekile ngoba usisiza siqonde ukuthi amakhemikhali anokwakheka okuhleliwe, kungakhathaliseki ukuthi avelaphi noma indlela yokulungiselela. Futhi wakha isisekelo sokunquma amafomula amakhemikhali amakhemikhali ahlukahlukene.
3. Umthetho Wezilinganiso Eziningi
UMthetho Wezilinganiso Eziningi, owatholakala nguJohn Dalton ekuqaleni kwekhulu le-19, uthi uma izakhi ezimbili zingakha inhlanganisela engaphezu kweyodwa, khona-ke ubuningi besakhi esisodwa obuhlanganiswe nesisindo esithile sesakhi esinye buzoba ngesilinganiso sezinombolo eziphelele ezilula.
Isibonelo:
Cabanga ngekhabhoni nomoya-mpilo, okungakha ama-compound amabili ahlukene: i-carbon monoxide (CO) kanye ne-carbon dioxide (CO₂). Ku-carbon monoxide, isilinganiso sekhabhoni nomoya-mpilo ngesisindo cishe singu-3:4, kuyilapho ku-carbon dioxide, isilinganiso sekhabhoni nomoya-mpilo ngesisindo cishe singu-3:8. Lesi silinganiso sibonisa ukuthi ku-CO₂ kanye ne-CO₂, inani lomoya-mpilo elihlanganiswe nesisindo esithile sekhabhoni lisesilinganisweni esingu-4:8, noma u-1:2.
Lo mthetho unikeza ukuqonda okubalulekile kokuthi ama-athomu ahlangana kanjani ngezilinganiso ezahlukene ukuze akhe ama-compounds ahlukahlukene, futhi usekela inkolelo-mbono kaDalton yama-athomu yokuthi izinto ezidaliwe zakhiwe ngama-athomu angahlukaniseki.
4. Umthetho kaGay-Lussac
Umthetho kaGay-Lussac, owaphakanyiswa nguJoseph Louis Gay-Lussac ngo-1808, uthi ekusabeleni kwamakhemikhali, amanani amagesi asabelayo kanye nalawo emikhiqizo yawo, uma elinganiswa ngokushisa okufanayo kanye nokucindezela, atholakala esilinganisweni sezinombolo ezilula eziphelele. Lo mthetho uvame ukubhekwa njengokwandiswa komthetho wezilinganiso eziqondile zokusabela kwegesi.
Isibonelo:
Uma sinokusabela phakathi kwe-hydrogen ne-oxygen ukuze sakhe amanzi, njengokuthi:
\[ 2H_2 (g) + O_2 (g) \umcibisholo ongakwesokudla 2H_2O (g) \]
Ngakho-ke amavolumu amabili egesi ye-hydrogen asabela ngevolumu eyodwa yegesi ye-oxygen ukuze akhiqize amavolumu amabili egesi yamanzi (umusi). Lokhu kubonisa ukuthi isilinganiso samavolumu amagesi asabelayo siyinombolo ephelele elula (2:1:2).
Lo mthetho ubaluleke kakhulu kumakhemikhali egesi futhi usiza ukuchaza ukuthi amagesi asebenzisana kanjani ekusabeleni kwamakhemikhali. Uphinde usize ekunqumeni umthamo we-molar wegesi kanye nomqondo we-mole kumakhemikhali.
Isiphetho
Le mithetho emine eyisisekelo yamakhemikhali—uMthetho Wokulondolozwa Kwesisindo, uMthetho Wezilinganiso Eziqondile, uMthetho Wezilinganiso Eziningi, kanye noMthetho kaGay-Lussac—iyizinsika ezibalulekile ekuqondeni kwethu ukusabela kwamakhemikhali kanye nokwakheka kwezinto. Ayigcini nje ngokuhlinzeka ngohlaka lokubikezela umphumela wokusabela kwamakhemikhali kodwa futhi iyasiza ekubalweni okunembile kwezibalo elabhorethri yamakhemikhali.
Ngokuqonda nokusebenzisa le mithetho, singawuqonda kangcono umhlaba osizungezile, kusukela ezinqubweni ezinkulu zezimboni kuya ezenzakalweni zemvelo zansuku zonke. Ziyisisekelo sokutholwa okuningi kanye nokusungula izinto ezintsha kumakhemikhali, okuqhubeka nokucindezela imingcele yolwazi lwabantu.
