Mene ne Gibbs makamashi

Maras wata-wata aiwatar a cikin wani bude da rufaffiyar irin tsarin da aka bayyana a cikin sharuddan na musamman da sharudda, da aka sani da Gibbs makamashi. Shi ne aikin da ke jihar. du Gibbs, aiki tare da thermodynamic tsarin, gudanar kawo shi ta hanyar da tabarbarewa, kuma enthalpy. Gibbs makamashi, musamman, ya sa ya yiwu a hango ko hasashen da shugabanci na kwarara daga maras wata-wata nazarin halittu tafiyar matakai da kuma kimanta su yadda ya dace a rubuce samuwa.

Idan muka yi amfani da Gibbs karshe na biyu thermodynamic doka, da halitta zai kasance da wadannan: akai (const) matsa lamba da kuma yawan zafin jiki ba tare da waje daukan hotuna tsarin zai iya taimaka wa maras wata-wata kwarara kawai don irin wannan tafiyar matakai, saboda abin da abin da yake a rage Gibbs makamashi matakin zuwa darajar da cewa faruwa a lokacin da ta kai ta ƙam m. Ma'auni wani thermodynamic tsarin yana nufin invariability na ce ikon (m). Saboda haka Gibbs makamashi ne m (free enthalpy) a isobaric-isothermal tsarin. Bari mu bayyana dalilin da ya sa shi ne kayyade m. A gaskiya wannan shi ne daya daga cikin mafi muhimmanci Buddah na ma'auni thermodynamic: ba jiha a zazzabi da kuma matsa lamba immutability nufin cewa ga na gaba canji wajibi ne a kara da matakin da makamashi, da kuma wannan mai yiwuwa ne kawai idan ka canza wani waje dalilai.

Letter nadi - G. numerically daidaita da bambanci tsakanin da aka sani enthalpy da tamanin da samfurin zafin jiki a kan entropy. Wannan ne da Gibbs makamashi za a iya bayyana ta hanyar da wadannan dabara:

G = H - (S * t),

inda S - entropy da tsarin. t - thermodynamic zazzabi. H - enthalpy. A entropy da tsarin a cikin sama dabara ne kunshe a domin la'akari da cewa high zazzabi rage ma'ana tsarin jihar (cuta) da kuma low - a kan m.

Tun da da Gibbs makamashi, enthalpy, da kuma - wasu daga cikin tsarin ayyuka a thermodynamic, ta canza G ko H za a iya halin da sinadaran canji da ke faruwa. Idan ba dauki lissafi da kuma Gibbs makamashi canji, to, shi nasa ne da aji na thermochemical.

Tare da girmamawa ga wannan makamashi iya tsara Rule Hess idan matsa lamba da kuma m zazzabi, halittar labari abubuwa na farko (na asali reagent) take kaiwa zuwa gaskiya cewa makamashi a cikin tsarin da aka canza, bayyanar da ke faruwa halayen da kuma lambar a kan sakamakon ɓãci.

Tun da makamashi ake a cikin labarin, shi ne m yawa, da manufar "misali Gibbs makamashi" da aka gabatar don yin lissafin. Wannan darajar ne ba a wani sinadaran kasida, numerically daidaita 298 KJ / mol (lura da cewa girma ne kamar kowane sauran makamashi matauni). Wannan darajar ba ka damar yin lissafi da canji a cikin kusan kowace tsarin sunadarai.

Idan a lokacin hanya na wani sinadaran dauki, wani waje mataki (aiki ne yake aikata) ya jũya a kan tsarin, sa'an nan da Gibbs free makamashi darajar ƙaruwa. Irin wannan halayen suna kira endergonic. Haka kuma, idan da tsarin kanta ya aikata aikin, ƙãrẽwar taskõkin makamashi, muna magana ne game da ekzergonicheskih manifestations.

A ra'ayi na Gibbs makamashi ya sami fadi da aikace-aikace a cikin zamani sunadarai. Alal misali, polymer kira dogara ne a kan Bugu da kari dauki. A irin hanyoyin da wasu barbashi an hada a cikin daya, da entropy darajar rage-rage. Bisa ga dabara Gibbs, shi za a iya bayar da hujjar cewa wani waje tasiri (msl, high zafin jiki) na iya biya irin exothermic Bugu da kari dauki, wanda aka tabbatar a yi.