Uyini ukushisa wokusabela

Nokho, Nakuba ujwayele igama elithi "enthalpy esezingeni kumiswa" livela iningi izifundo yokuthakwa kwamakhemikhali, isetshenziswa kabanzi. Kunzima ukucabanga yimuphi umkhakha womsebenzi, akunakwenzeka ukuthi básebenzisa lesi simanga.

Nasi isibonelo nje ezinye zazo, lapho kuyadingeka ukuze nazi ukuthi liyini ukushisa wokusabela. Okwamanje, umkhakha imoto ethuthuka ngesilinganiso kumnandi: inani imishini kwandisa izikhathi eziningana ngonyaka. Kulokhu, lo main amandla umthombo wabo uphethiloli (ukuthuthukiswa okunye namanje lapho evuma yayo kuphela prototypes ambalwa). Ukuze ulungise agqoke fuel amabutho zisebenzisa izithasiselo ekhethekile ukunciphisa ukushuba detonation. Isibonelo esimangalisayo - monomethylaniline. Phezu kokuthola ibalwa ukushisa yokusabela, okuyinto kulokhu -11-19 kJ / Mol.

Esinye isici esibangela isicelo - umkhakha ukudla. Ngokungangabazeki, ubani owayinaka inkomba ikhalori lomkhiqizo. Kulokhu, ukushisa calorific ukuthi bayavuma futhi kuhlobane ngokuqondile kusukela ukushisa ezikhishwe phakathi namachibi ukudla. Ukulungisa Ukudla yakho isekelwe la idatha, kungenzeka ukuba sifinyelele ukuncipha eziphawulekayo isisindo emzimbeni. Naphezu kweqiniso lokuthi kuye kwaba nokuvutha ukuphendula ulinganiswa Joules, ama-calories, futhi phakathi kwawo kukhona ubuhlobo ngqo: 4 J = 1 kcal. inani elilinganisiwe (isisindo) ngokuvamile ecacisiwe maqondana nokudla.

Ake Manje sengibuyela ithiyori ukunikeza incazelo. Ngakho-ke, umphumela ezishisayo likhombisa inani ukushisa yakhululwa noma amuncwa uhlelo, ukugeleza kuwo yezinqubo zamakhemikhali. Kumele kukhunjulwe ukuthi ngaphezu emisebeni ukushisa kungaba elakhiwe. enthalpy emgomeni Ukwakheka ngamanani alinganayo Ngokuphathelene nomahluko okhona egameni amazinga amandla kohlelo: kokuqala futhi asalile. Uma ukusabela kwenzeka ukuncela yokushisa okuvela imvelo, thina-ke khuluma inqubo endothermic. Ngakho, amandla ukushisa ukukhulula isici exotherm. Ziyakwazi kulula ngempela ukuhlukanisa uma ukubaluleka amandla Imininingwane ezikhishwe ngenxa yokusabela, kukhulu kunesono kudliwe kwayo (isibonelo, i-energy ezishisayo kukaphethiloli evutha), lokhu exotherm. Kodwa amanzi noqhekeko ku-hydrogen ne-carbon futhi carbon monoxide kudingekile ukusebenzisa amandla xaxa Ukushisa, ngakho ngoba kunesithembiso ukumuncwa yayo (endothermy).

Bala ukushisa wokusabela ngokusebenzisa amafomula ezaziwayo. Ngo izibalo, umphumela ezishisayo luchazwa ngegama Q (noma DH). Umahluko kulokho uhlobo inqubo (Endo noma Exo), ukuze Q = - DH. zibalo Thermochemical lokucabanga inkomba umphumela ezishisayo kanye reagents (kweqiniso futhi ukubala reverse). I engavamile kulezi zibalo kungenzeka ukuguquguquka ubukhulu imiphumela ezishisayo kanye izinto ngokwabo ezingxenyeni ezahlukene. Mhlawumbe ukukhupha termwise noma kwalokho amafomula ngokwabo, kodwa zithi wokuhlanganisa izinto.

Nasi isibonelo ukusabela methane amandla omlilo, carbon, i-hydrogen:

1) CH4 + 2O2 = CO2 + 2H2O + 890 kJ

2) C + O2 = CO2 + 394 kJ

3) 2H2 + O2 = 2H2O + 572 kJ

Manje susa u-2 no-3 1 (ohlangothini lwesokunene kwesokudla, kwesokunxele - ukusuka kwesobunxele).

Ngenxa yalokho, sithola:

CH4 - C - 2 H4 = 890 - 394 - 572 = - 76 kJ.

Uma zonke izingcezu iphindwe - 1 (ukususa value e-negative), sithola:

C + 2H2 = CH4 + 76 kJ / Mol.

Umuntu 'angenziwa kanjani humusha imiphumela? Umthelela ezishisayo ukuthi kwenzeka ngesikhathi kumiswa methane kusuka carbon ne-hydrogen, eneminyaka engu-76 J imvukuzane gas ngomkhiqizo ngamunye. Futhi kusukela amafomula ukuthi energy ezishisayo bayokhululwa, okungukuthi, sikhuluma inqubo exothermic. izibalo Okufanayo ungagwema isidingo ucwaningo laboratory ngokushesha ukuthi ngokuvamile zinzima.