Ho utloisisa Enthalpy le Entropy
Ho khemistri le thermodynamics, enthalpy le entropy ke mehopolo e 'meli ea motheo ea bohlokoa ho utloisiseng hore na litsamaiso tsa matla li sebetsa joang. Li bapala karolo ea bohlokoa liketsong tse fapaneng tsa lik'hemik'hale, lits'ebetsong tsa 'mele, esita le mahlaleng a matla a tsosolositsoeng. Sengoloa sena se tla hlalosa enthalpy le entropy ka botebo le hore na li sebelisana joang maemong a fapaneng.
Ho utloisisa Enthalpy
Tlhaloso ea Enthalpy
Enthalpy ke thepa ea thermodynamic e sebelisetsoang ho lekanya kakaretso ea matla tsamaisong, ho kenyeletsoa matla a ka hare le matla a nang le sebopeho sa khatello le bophahamo. Enthalpy hangata e tšoantšetsoa ke tlhaka \( H \) 'me e lekanngoa ka li-unit tsa joules (J) Tsamaisong ea Machaba (SI).
Ka lipalo, enthalpy e ka hlalosoa e le:
\[ H = U + PV \]
moo \( U \) e leng matla a ka hare a sistimi, \( P \) ke kgatello, mme \( V \) ke bophahamo ba modumo.
Mosebetsi oa Enthalpy Likarabelong tsa Lik'hemik'hale
Moelelong oa lik'hemik'hale, phetoho ea enthalpy (\( \Delta H \)) e bontša hore na karabelo ke exothermic (energy e lokollang ka mokhoa oa mocheso) kapa endothermic (energy e monyang). Haeba \( \Delta H \) e le mpe, karabelo ke exothermic; haeba \( \Delta H \) e le ntle, karabelo ke endothermic.
Mohlala, ho chesoeng ha peterole e kang methane (\( CH_4 \)):
\[ CH_4 + 2O_2 \motsu o ka ho le letona CO_2 + 2H_2O + matla \]
Karabelo ena e lokolla matla, kahoo e na le \( \Delta H \) e mpe.
Tekanyo ea Enthalpy
Ho bohlokoa ho hopola hore re ke ke ra lekanya enthalpy e felletseng ea sistimi, empa re ka lekanya phetoho ho enthalpy (\( \Delta H \)). Litekong tsa laboratori, liphetoho tsa enthalpy hangata li lekanngoa ho sebelisoa calorimetry, ke hore, ka ho lekanya bongata ba mocheso o lokollotsoeng kapa o monngoang nakong ea karabelo.
Ho utloisisa Entropy
Tlhaloso ea Entropy
Entropy ke tekanyo ea pherekano kapa pherekano tsamaisong. Ho thermodynamics, entropy hangata e tšoantšetsoa ke tlhaka \( S \) mme e boetse e lekanngoa ka diyuniti tsa joules ka kelvin (J/K) Tsamaisong ea Machaba (SI). Khopolo ea entropy e ile ea hlahisoa ka lekhetlo la pele ke setsebi sa fisiks sa Lejeremane Rudolf Clausius lekholong la bo19 la lilemo.
Entropy e tšoantšetsoa ke equation:
\[ \Delta S = \frac{q_{rev}}{T} \]
moo \( \Delta S \) e leng phetoho ho entropy, \( q_{rev} \) e leng mocheso o fetisetswang tshebetsong e ka fetolwang, mme \( T \) e le mocheso o feletseng.
Molao-motheo oa Entropy ho Thermodynamics
E 'ngoe ea melao-motheo ea motheo ea thermodynamics ke hore bokahohle bo sekamela ho eketseheng ha entropy. Ka mantsoe a mang, lits'ebetso tsa tlhaho li lula li lebisa ho eketseheng ha pherekano kapa pherekano. Molao-motheo ona o tsejoa e le Molao oa Bobeli oa Thermodynamics.
Entropy Likarabelong tsa Lik'hemik'hale
Moelelong oa lik'hemik'hale, phetoho ea entropy (\( \Delta S \)) e re bolella hore na lihlahisoa tsa karabelo li hlophisitsoe hantle kapa li sa hlophiseha ha li bapisoa le li-reactant. Haeba \( \Delta S \) e le ntle, lihlahisoa li sa hlophiseha haholo; haeba \( \Delta S \) e le mpe, lihlahisoa li hlophisitsoe haholoanyane.
Mohlala o tloaelehileng o sebelisoang ho hlalosa khopolo ena ke ho kopanya likhase tse peli. Ha likhase tse peli li kopantsoe, entropy eohle ea sistimi ea eketseha hobane limolek'hule tsa khase lia qhalana le ho senyeha haholoanyane.
Tšebelisano Pakeng tsa Enthalpy le Entropy: Mosebetsi oa Gibbs
Ho utloisisa ka botlalo kamoo enthalpy le entropy hammoho li amang liketso tsa lik'hemik'hale le lits'ebetso tsa thermodynamic, re tlameha ho sheba mosebetsi oa Gibbs kapa matla a mahala a Gibbs, a hlalosoang ke \( G \).
Matla a mahala a Gibbs a hlalosoa e le:
\[ G = H – TS \]
moo \( H \) e leng enthalpy, \( T \) ke mocheso o feletseng, 'me \( S \) ke entropy.
Phetoho ea matla a mahala a Gibbs (\( \Delta G \)) e fana ka sesupo sa ho iketsahalla ha ts'ebetso kapa karabelo. Haeba \( \Delta G \) e le mpe, ts'ebetso e tla etsahala ka boiketsetso. Haeba \( \Delta G \) e le ntle, ts'ebetso e ke ke ea etsahala ka boiketsetso. Haeba \( \Delta G \) e le lefela, sistimi e leka-lekane.
Nyeoe ea mohlala
A re nahaneng ka mokhoa oa ho qhibilihisa leqhoa hore e be metsi ka mocheso oa 0°C (273.15 K):
\[ H_2O_{(s)} \motsu o nepahetseng H_2O_{(l)} \]
Mokgweng ona, ho na le phetoho ya enthalpy (\( \Delta H \)) hobane ho hlokahala matla ho roba maqhama a leqhoa. Hape ho na le phetoho ya entropy (\( \Delta S \)) hobane metsi a metsi a na le moferefere ho feta leqhoa.
Phetoho ea enthalpy bakeng sa leqhoa le qhibilihang e ka ba +6.01 kJ/mol, 'me phetoho ea entropy e ka ba +22.0 J/K·mol. Re ka bala \( \Delta G \) ho fumana ho iketsahalla ha ts'ebetso:
\[ \Delta G = \Delta H – T \Delta S \]
Ho 0°C (273.15 K):
\[ \Delta G = 6010 – 273.15 \makgetlo a 22 \]
\[ \Delta G = 6010 – 6009.3 \hoo e ka bang 0.7 \mongolo{ J/mol} \]
Kaha \( \Delta G \) e haufi le lefela, sena se bontsha hore tshebetso ya ho qhibilihisa leqhoa ka 0°C e leka-lekane.
Bohlokoa Bophelong ba Letsatsi le Letsatsi
Ho utloisisa enthalpy le entropy ho bohlokoa likarolong tse fapaneng tsa bophelo ba motho, ho tloha theknolojing ho ea saenseng ea bophelo bo botle. Mohlala, indastering ea lijo, mekhoa ea ho pheha le ho boloka hangata e kenyelletsa ho laola liphetoho tsa enthalpy le entropy ho boloka boleng ba lijo. Mahlaleng a matla a tsosolositsoeng, joalo ka lisele tsa letsatsi le libeteri, tlhahlobo ea thermodynamic e thusa ho ntlafatsa bokhoni le ts'epo.
Ho phaella moo, maemong a tikoloho, melao-motheo ea enthalpy le entropy e ka sebelisoa ho utloisisa lits'ebetso tsa tlhaho tse kang potoloho ea metsi, photosynthesis le phetoho ea tlelaemete. Tsebo ena e boetse e thusa ho rala mahlale le maano a ho fokotsa litlamorao tse mpe tikolohong.
Qetello
Enthalpy le entropy ke mehopolo e 'meli e amanang ea thermodynamic e leng ea bohlokoa bakeng sa ho utloisisa lits'ebetso tse fapaneng tsa lik'hemik'hale le tsa 'mele. Enthalpy e amana le matla ohle a sistimi, ha entropy e bonts'a tekanyo ea pherekano kapa pherekano. Tšebelisano lipakeng tsa enthalpy le entropy, joalo ka ha e lekantsoe ke mosebetsi oa Gibbs, e fana ka temohisiso ea bohlokoa mabapi le ho iketsahalla le ho leka-lekana ha lits'ebetso tsa thermodynamic. Ho utloisisa likhopolo tsena ha ho bohlokoa feela khopolo-taba empa hape ho na le lits'ebetso tse sebetsang theknolojing, indastering le bophelong ba letsatsi le letsatsi.
