Umthetho wokuqala we-thermodynamics ukuqala kwakho konke okukhona

Isihloko sokutadisha i-thermodynamics ingamandla kuwo wonke ukubonakala kwawo futhi, okubaluleke kakhulu, ukuguqulwa kwamandla kusuka kwesinye isilwane kuya kwesinye. Kwenzeke ukuthi leli gama ngokwayo lavela ekuqaleni kocwaningi lwesayensi emkhakheni wezamandla, futhi ngaleso sikhathi uhlu lwamandla ahlukahlukene ayenesisindo esincane - luyimishini futhi lushisa. Ngakho-ke, igama elithi "thermodynamics" liye labonisa ngokunembile isisekelo senkulumo - ukunyakaza (ukudluliselwa) kanye nokuguqulwa kokushisa kube yinto yokusebenza futhi ngokuphambene. Kancane kancane kwakukhona imiqondo ekhombisa izinqubo ezishisayo: ukushisa kwe-fusion, amandla okushisa futhi, ekugcineni, iyunithi yokulinganisa inani lokushisa - ikhalori (1772, uMilke). Isikhathi esiningi sizodlula futhi umthetho wokuqala we-thermodynamics uzokwakhiwa, kodwa isinyathelo ngasinye sasiwumphumela womsebenzi wobuciko wabacwaningi abaningi.

Ukutadisha imithetho ye-thermodynamics , imihlangano ethile iye yamukelwa eyenza kube lula ukuhlukanisa into ehlolisiswayo nokucacisa izindawo zayo okufanele zifundwe. Izinto eziphenywayo zimelelwa njengezinhlelo ezivaliwe ezivela kunani elikhulu lamazinhlayiyana. Uma kusistimu kungenzeka ukuthi unqume imingcele yombhalo othize, bese kuthiwa umzimba. Yilokho okubambe iqhaza eliyinhloko kwesenzo se-thermodynamic: uhlelo lwezinhlayiya, olufakwe emvolweni othile, liwugesi oluhle. Ngendlela yokuguqulwa kwamandla, uhlelo lwe-thermodynamic lushintsha isimo sawo, futhi lezi zinguquko zichazwa yiqoqo lemiqondo - izinqubo zemigomo. Uma izinga lokushisa T, ivolumu V ne-pressure P zithathwa njengemingcele, zanele ukuchaza noma iyiphi inqubo ye-thermodynamic. Zonke izinhlelo zibhekwa njengezizwe kuphela zokulingana. Ukusungula i-equilibrium, isibonelo, ukushisa, inqubo yokudlulisa ukufudumala - into ihlehlisa phansi, futhi into iyathukuthela. Ngesikhathi esifanayo, ubungakanani "obunikezwayo", njengoba umthetho wokuqala we-thermodynamics uthi, kuzoba okufanayo. Futhi lapha kukhona umsebenzi oyinhloko ososayensi abaxazulula ngawo amakhulu eminyaka: ukusesha abahlanganyeli ekushintsheni kwamandla kanye nencazelo yendima yabo kule nqubo.

Isisekelo sezinsiza zemfundiso ye-thermodynamics yimithetho emithathu. Kucatshangwa ukuthi umzimba ungathatha amandla ngokwandisa ngaphakathi kwawo (isibonelo, ukufudumala) kanye / noma ngenxa yamandla ayo angaphakathi okusebenza ekunqobeni amandla angaphandle (isibonelo, ukuphoqa i-piston). Ukuqhubeka kulokhu, umthetho wokuqala we-thermodynamics uhunyushwa ngale ndlela: ukuguqulwa kwamandla angaphakathi omzimba u-U kungumthamo wamandla Q abanjwe wona kanye namandla emandla angaphandle A. Ngokwezibalo, lokhu kuboniswa ngokwezinguquko ezingenamkhawulo kanje:

DU = dQ + dA (1)

Eqinisweni, lo ngumthetho wokulondoloza amandla, singasho ukuthi, umthetho wokuba.

Ukuzikhethela kwezinqubo ze-thermodynamic kuvame ukubhekwa emfanekisweni lapho igesi elihle lithathwa ngumzimba osebenzayo, ongashiswa futhi / noma osebenza ngamandla angaphandle (ukucindezela-ukwanda) nge-piston, kanye neminye yemingcele - ukucindezela P, ivolumu V noma izinga lokushisa T Ilingana nokuhlala njalo. Ukusetshenziswa komthetho wokuqala we-thermodynamics ukuphumelela kwenza kube lula ukuthola imithombo yamamukeli wezamandla ngezimo ezithile.

Inqubo ye-isochoric isho ukuthi V = const. Umphumela wukuthi umsebenzi womsebenzi awutholakali, ngoba Ivolumu ayishintshi, kuphela amandla angaphakathi ashintshwe ngenxa yokushisa , bese: dA = pdV = 0, ngakho-ke dU = dQ futhi ingathathwa kusuka ebuhlotsheni:

I-DQ = (m / M) * I-CV * dT (2)

Ngakho-ke, inqubo ye-isochoric ingenxa yokunyuka kwamazinga okushisa.

Inqubo ye-isobaric ithatha i-p = const, futhi lesi simo sifinyelelwe uma isikhungo sokusebenza senza umsebenzi wokushisa ngokushisa, isibonelo, ukuhambisa i-piston. Uma sisebenzisa ezinye izinkulumo zokushisa amandla kanye nokulinganisa kwe-Mendeleev-Klaiperon, singakwazi kalula ukuthola inkulumo yokubala umsebenzi womshini wegesi :

A = (m / M) * R * (T2-T1) (3)

R is njalo gas, futhi kusho umsebenzi ukwandisa umthamo kagesi inani lemvukuzane, uma izinga lokushisa lishintsha nge degree elilodwa Kelvin. Isiphetho: ngenqubo ye-isobaric, igesi igcwaliswa amandla okushisa (2) futhi idla ingxenye yenyuka yangaphakathi ngaphakathi ngokukhuliswa (3).

Inqubo lapho iT = const, e-thermodynamics ibizwa ngokuthi i-isothermal. Ingqikithi yayo ikhona ukuthi amandla angaphakathi atholakele ngenxa yokushisa asetshenziselwa ukusebenza ukuze anqobe amandla angaphandle. Umthetho wokuqala we-thermodynamics wokushona kwemvelo uphakamisa ukuthi ukuze kugcinwe izinga lokushisa lomzimba, amandla alo angaphakathi akhiqiza izindleko zokwenza umsebenzi wokusebenza futhi kuxhomeke ekushintsheni kokucindezela. Bala lezi zindleko zamandla zingabonakala kusuka enkulumweni:

Q = A = (m / M) * R * T * (ln (p1 / p2)).