Kodi kutentha anachitazi

Ngakhale ankadziwa mawu akuti "muyezo enthalpy mapangidwe" akupezeka ambiri maphunziro zimapangidwira, Komabe, ntchito zambiri ndipo anthu ambiri. N'zovuta kulingalira dera lililonse kuchita zomwe sibwenzi ntchito zodabwitsazi.

Pano pali chitsanzo cha ena mwa iwo, chimene chili chofunika basi mudziwe kutentha anachita. Panopa, makampani galimoto kusiyana pa mtengo wosangalatsa: chiwerengero cha makina kumawonjezera kangapo pa chaka. Pankhaniyi, mphamvu yaikulu gwero kwa iwo ndi mafuta (chitukuko zina akali kuzindikira ake okha mu prototypes ochepa). Kusintha zikuthwanima mphamvu mafuta ntchito zina mwapadera kuti kuchepetsa mphamvu ya detonation lapansi. A chitsanzo chapadera - monomethylaniline. Pa chiphaso masamu kutentha anachita, zomwe mu nkhani iyi ndi -11-19 KJ / mol.

Wina dera ntchito - adzasowa chakudya. Mosakayikira, aliyense amene anamvetsera kwa calorie umboni wa malonda. Mu nkhani iyi, calorific kutentha zotani ndi mwachindunji zokhudzana kuyambira kutentha anamasulidwa pa makutidwe ndi okosijeni chakudya. Kusintha zakudya zanu zochokera deta awa, n'zotheka kukwaniritsa kuchepetsa kwambiri thupi. Ngakhale kuti kutentha zotani amayezedwa joules, zopatsa mphamvu, ndi pakati pa iwo pali kugwirizana: 4 J = 1 kcal. pafupifupi kuchuluka (kulemera) nthawi mwachindunji poyerekezera ndi zakudya.

Tsopano tiyeni kuti chiphunzitso ndi kupereka tanthauzo a. Choncho, zotsatira matenthedwe limasonyeza kuchuluka kwa kutentha anamasulidwa kapena chosakanikirana ndi dongosolo, otaya mu izo mankhwala zako. Ziyenera adzanyamula kukumbukira kuti kuwonjezera kutentha cheza akhoza kwaiye. Standard enthalpy mapangidwe ndi numerically wofanana ndi kusiyana pakati zimatiyika mphamvu ya dongosolo: koyamba ndi yotsalira. Ngati zimene kumachitika kuyamwa kutentha kwa chilengedwe, ndiye ife tikuyankhula za ndondomeko endothermic. Choncho, kutentha mphamvu kumasula khalidwe exotherm. Iwo N'zosavuta kusiyanitsa ngati mtengo wa mphamvu yonse anamasulidwa chifukwa cha zimene ali wamkulu kuposa kuti chimadyedwa chiyambi chake (mwachitsanzo, mphamvu matenthedwe wa mafuta moto), exotherm izi. Koma chifukwa madzi kuwonongeka mu hydrogen ndi mpweya ndi mpweya monoxide zofunika amaika mphamvu zowonjezera Kutentha, kotero zikupereka mayamwidwe ake (endothermy).

Kuwerengetsa kutentha zotani pogwiritsa ntchito mitunduyi kudziwika. Mu anapezazo ndi, zotsatira matenthedwe ndiwo amaimira Q (kapena DH). Kusiyana kwa mtundu wa ndondomeko (endo kapena exo), kotero kuti Q = - DH. maikwezhoni Thermochemical kuganiza kumasonyeza mmene matenthedwe ndi reagents (woona ndi mawerengedwe n'zosiyana). The peculiarity wa maikwezhoni izi mu kuthekera kwa kusuntha ukulu wa zotsatira matenthedwe ndi zinthu okha m'madera osiyanasiyana. Mwina termwise wochotsera kapena Kuwonjezera mitunduyi okha, koma ndi madera a loitanirana zinthu.

Pano pali chitsanzo cha zochita za dziko kuyaka, mpweya wa hydrogen:

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

2) C + O2 = CO2 + 394 KJ

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

Tsopano kuchotsera 2 ndi 3 cha 1 (kumanja ya kumanja, kumanzere - kuchokera kumanzere).

Chifukwa, ife kupeza:

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

Ngati zidutswa zonse kuchulukitsa ndi - 1 (kuchotsa kufunika zoipa), ife kupeza:

C + 2H2 = CH4 + 76 KJ / mol.

Kodi m'modzi amasulire zotsatira? Mmene matenthedwe kuti zidzachitika mapangidwe dziko kwa mpweya ndi wa hydrogen, zaka 76 J pa Mole mpweya mankhwala. Komanso ku mitunduyi kuti mphamvu matenthedwe adzamasulidwa, ndiko kuti, tikulankhula za ndondomeko exothermic. kuwerengetsera ofanana angapewe kufunika zatsopano yomweyo zasayansi kuti ndi mavuto ambiri.