Phetoho ea Enthalpy le Enthalpy
Selelekela ho Enthalpy
Enthalpy ke mohopolo oa bohlokoa oa thermodynamic k'hemistring le fisiks. Lentsoe enthalpy le tsoa lentsoeng la Segerike la boholo-holo le bolelang "ho futhumatsa ka hare" (en e bolelang "ka hare" le thalpein e bolelang "ho futhumatsa"). Khopolo ena e ile ea hlahisoa ka lekhetlo la pele ke setsebi sa fisiks sa Madache Heike Kamerlingh Onnes mathoasong a lekholo la bo20 la lilemo. Ka mantsoe a bonolo feela, enthalpy e hlalosa kakaretso ea matla tsamaisong e khonang ho etsa mosebetsi ka khatello e sa khaotseng.
Ka lipalo, enthalpy (H) e hlalosoa ka tsela e latelang:
\[ H = U + PV \]
Hokae
– \( H \) ke enthalpy,
– \( U \) ke matla a ka hare a sistimi,
– \( P \) ke kgatello, mme
– \( V \) ke bophahamo ba modumo.
Enthalpy ke thepa e pharaletseng, ho bolelang hore boleng ba eona bo itšetlehile ka bongata ba lintho tse teng tsamaisong. E bohlokoa haholo lits'ebetsong tsa thermodynamic le liketsong tsa lik'hemik'hale hobane phetoho ea enthalpy e ka sebelisoa ho fumana hore na ke matla a makae a lokolloang kapa a monngoang ts'ebetsong.
Karolo ea Enthalpy Likarabelong tsa Lik'hemik'hale
Nakong ea karabelo ea lik'hemik'hale, litlamo tsa lik'hemik'hale pakeng tsa liathomo le limolek'hule lia robeha 'me lia fetoloa. Ts'ebetso ena e kenyelletsa phetoho ea matla a ka lokolloang kapa a monngoang ke sistimi. Matla ana hangata a lekanngoa ka phetoho ea enthalpy (\( \Delta H \)).
Haeba phetoho ea enthalpy e le mpe (\( \Delta H < 0 \)), karabelo ke exothermic, ho bolelang hore e ntša matla tikolohong. Mohlala o tloaelehileng oa karabelo ea exothermic ke ho cha, moo mafura a arabelang le oksijene ho hlahisa mocheso le leseli.
Ka lehlakoreng le leng, haeba phetoho ea enthalpy e le ntle (\( \Delta H > 0 \)), karabelo ke ea endothermic, ho bolelang hore e monya matla a tsoang tikolohong. Mohlala oa karabelo ea endothermic ke photosynthesis, moo limela li monyang matla a letsatsi ho fetola carbon dioxide le metsi hore e be glucose le oksijene.Ho Bala Phetoho ea Enthalpy
Ho bala phetoho ea enthalpy karabelong ea lik'hemik'hale, hangata re sebelisa data ea calorimetric kapa molao oa Hess. Phetoho e tloaelehileng ea enthalpy (\( \Delta H^\circ \)) ke phetoho ea enthalpy ea karabelo e hlahang khatellong ea 1 atm le mocheso o itseng (hangata 25°C kapa 298 K).
Lintlha tsa Khalorimetry
Calorimetry ke mokhoa oa liteko o sebelisoang ho lekanya boholo ba mocheso o amehang karabelong ea lik'hemik'hale. Sesebelisoa se sebelisitsoeng tekong ena se bitsoa calorimeter. Re sebelisa calorimeter, re ka lekanya phetoho ea mocheso e etsahalang nakong ea karabelo, e ka fetoloang phetoho ea enthalpy.
Molao oa Hess
Molao oa Hess o re phetoho e felletseng ea enthalpy ea karabelo ea lik'hemik'hale ha e itšetlehe ka tsela eo e e nkang, empa e itšetlehile feela ka maemo a pele le a ho qetela. Sena se bolela hore re ka sebelisa lintlha tse tsejoang ho tsoa mekhahlelong e fapaneng ea karabelo ho bala phetoho e felletseng ea enthalpy. Mohlala, haeba karabelo e ka aroloa ka mehato e 'maloa e menyenyane ka liphetoho tse tsejoang tsa enthalpy, re ka akaretsa li-enthalpy tsa mohato o mong le o mong ho fumana phetoho e felletseng ea enthalpy.
Molao oa Hess o ka hlalosoa ka mokhoa o bonolo:
\[ \Delta H_{\text{total}} = \sum \Delta H_{\text{reaction}} \]
Litšebeliso tsa Enthalpy indastering
Mehopolo ea liphetoho tsa enthalpy le enthalpy e bohlokoa haholo indastering e fapaneng, haholo-holo tse amanang le matla le lik'hemik'hale. Mesebetsi e meng ea bohlokoa e kenyelletsa:
Indasteri ea Matla
Indastering ea tlhahiso ea matla, ebang ke mafura a khale, matla a nyutlelie, kapa matla a nchafatsoang, katleho ea sistimi e itšetlehile haholo ka enthalpy. Mohlala, setsing sa motlakase sa mouoane, katleho ea thermodynamic e khethoa ke phapang ea enthalpy pakeng tsa ho kenella (hangata metsi a metsi) le tlhahiso (mouoane o chesang haholo). Ho ntlafatsa phetoho ena ea enthalpy ho ka ntlafatsa katleho ea matla ka kakaretso.
Industri Kimia
Indastering ea lik'hemik'hale, ho utloisisa liphetoho tsa enthalpy ho bohlokoa bakeng sa ho rala lits'ebetso tse sebetsang hantle le ho laola likarabelo tsa exothermic kapa endothermic. Mohlala, tlhahisong ea ammonia ka ts'ebetso ea Haber, liphetoho tsa enthalpy li sebelisoa ho bolela esale pele le ho laola maemo a karabelo ho fihlela chai e ntle ka ho fetisisa.
Indasteri ea Lijo le Meriana
Liindastering tsa lijo le meriana, liphetoho tsa enthalpy li sebelisoa ho rala le ho ntlafatsa lits'ebetso tse kang ho pasteurization, sterilization le ho omisa. Ts'ebetso tsena hangata li hloka taolo e tiileng ea mocheso ho netefatsa polokeho le boleng ba sehlahisoa, kahoo kutloisiso e ntle ea liphetoho tsa enthalpy ea hlokahala.
Thuto ea Nyeoe: Phetoho ea Enthalpy Ts'ebetsong ea Haber
Mokhoa oa Haber ke mohlala o motle oa kamoo liphetoho tsa enthalpy li sebelisoang indastering ea lik'hemik'hale. Mokhoa ona o sebelisetsoa ho hlahisa ammonia (\( NH_3 \)) ho tsoa ho naetrojene (\( N_2 \)) le haeterojene (\( H_2 \)).
Likarabelo tsa lik'hemik'hale tse hlahang ke:
\[ N_2 (g) + 3 H_2 (g) \motsu o letona 2 NH_3 (g) \]
Karabelo ena ke exothermic ka phetoho e tloaelehileng ea enthalpy ea hoo e ka bang \( \Delta H = -92.4 \, \text{kJ/mol} \). Ka ho tseba hore karabelo ena e lokolla matla, baenjiniere ba lik'hemik'hale ba ka rala reactor ho laola mocheso o lokolloang le ho eketsa chai ea ammonia.
Qetello
Liphetoho tsa enthalpy le enthalpy ke likhopolo tsa motheo ho thermodynamics le k'hemistri tse re thusang ho utloisisa le ho laola matla tsamaisong. Ho tloha liketsong tse bonolo tsa lik'hemik'hale ho ea lits'ebetsong tse rarahaneng tsa indasteri, liphetoho tsa enthalpy li bapala karolo ea bohlokoa ho bolokeng matla le katlehong. Ka ho utloisisa le ho sebelisa likhopolo tsena, re ka rala lits'ebetso tse betere, tse sebetsang hantle le tse mosa tikolohong ho pholletsa le liindasteri tse fapaneng.
