Ukuqonda Ukusabela Okungavamile Nokungapheli
Ukusabela kwamakhemikhali kuyisenzakalo esibalulekile esivame ukuhlangana naso ekuphileni kwansuku zonke. Akwenzeki nje kuphela emalabhorethri kodwa nasezinqubweni ezahlukahlukene ezenzeka eduze kwethu, njengokupheka, ukufudumeza, ukushisa uphethiloli, ngisho nangaphakathi emizimbeni yethu. Ukusabela kwamakhemikhali kungahlukaniswa ngezigaba ezahlukene. Esinye sezibaluleke kakhulu sisekelwe ekutheni ukushisa kuyakhishwa noma kuyamuncwa ngesikhathi sokusabela. Kulesi simo, ukusabela kwamakhemikhali kungahlukaniswa ngezinhlobo ezimbili eziyinhloko: i-exothermic kanye ne-endothermic.
Ukuqonda Ukusabela Okungavamile
Ukusabela kwe-exothermic kungukusabela kwamakhemikhali okukhipha amandla ngesimo sokushisa endaweni ezungezile. Lawa mandla angavela ngesimo sokukhanya, ukushisa, noma kokubili. Le nqubo ingabonakala ngokushesha ngokwandisa izinga lokushisa endaweni yokusabela. Isibonelo esivame kakhulu sokusabela kwe-exothermic ukushiswa kukaphethiloli, njengokhuni, igesi, noma uwoyela. Lapho la mafutha esha, amandla ngesimo sokushisa akhishwa endaweni ezungezile.
Isici salokhu kusabela ukuthi i-enthalpy yemikhiqizo iphansi kune-enthalpy ye-reactants. Lokhu kusho ukuthi amandla akhishwa lapho imikhiqizo yakheka makhulu kunamandla adingekayo ukuphula izibopho kuma-reactants. Esinye isibonelo inqubo yokuphefumula ezintweni eziphilayo, lapho i-glucose iphulwa khona ngosizo lwe-oxygen ukuze ikhiqize i-carbon dioxide, amanzi, kanye namandla.
Izibonelo Zokusabela Okungavamile:
1. Ukusha kweMethane:
CH₄ + 2O₂ → CO₂ + 2H₂O + amandla (ukushisa)
2. Ukusabela phakathi kwe-asidi nesisekelo:
I-HCl(aq) + i-NaOH(aq) → i-NaCl(aq) + i-H₂O + amandla (ukushisa)
Empilweni yansuku zonke, singabhekana nokusabela okubangelwa ukushisa okukhulu enkambisweni yokushisa izinkuni esitofini noma esitofini, kanye nasezinhlotsheni ezahlukene zokusabela okudala ukushisa, njengeziqhumane zomlilo kanye nokuqhuma kwama-dynamos.
Ukuqonda Ukusabela Kwe-Endothermic
Ukusabela kwe-endothermic kuphambene nokusabela kwe-exothermic. Lokhu kusabela kumunca amandla avela endaweni ezungezile ngesimo sokushisa. Ngenxa yalokho, izinga lokushisa lendawo ezungezile liyancipha. Amandla amuncwa yi-reactants asetshenziselwa ukuphula izibopho zamakhemikhali ezindala bese kwakheka ezintsha. Ukusabela kwe-endothermic ngokuvamile kudinga amandla engeziwe ukuze kuqedwe kune-exothermic reactions.
Isici salokhu kusabela ukuthi i-enthalpy yemikhiqizo inkulu kune-enthalpy ye-reactants. Lokhu kusho ukuthi kudingeka amandla amaningi ukuze kuphulwe izibopho kuma-reactants kunalawo akhishwa lapho kwakheka imikhiqizo. Ukusabela kwe-endothermic kuvame ukutholakala ezinqubweni zemvelo, njenge-photosynthesis ezitshalweni.
Izibonelo Zokusabela Kwe-Endothermic:
1. Ukwenziwa kwe-Photosynthesis:
6CO₂ + 6H₂O + amandla (avela elangeni) → C₆H₁₂O₆ + 6O₂
2. Ukubola kwe-calcium carbonate:
I-CaCO₃(s) + amandla (ukushisa) → I-CaO(s) + I-CO₂(g)
Ku-photosynthesis, izitshalo zimunca amandla avela elangeni ukuze ziguqule i-carbon dioxide namanzi kube yi-glucose nomoya-mpilo. Le nqubo ibalulekile empilweni eMhlabeni ngoba yakha isisekelo sochungechunge lokudla.
Umehluko Obalulekile Phakathi Kokusabela Kwe-Exothermic kanye ne-Endothermic
Ngemva kokuqonda izincazelo eziyisisekelo kanye nezibonelo zalezi zinhlobo ezimbili zokusabela kwamakhemikhali, ake sihlole umehluko omkhulu phakathi kokusabela kwe-exothermic kanye ne-endothermic:
1. Amandla:
– Ukusabela kwe-exothermic kukhulula amandla endaweni ezungezile, kuyilapho ukusabela kwe-endothermic kudonsela amandla endaweni ezungezile.
2. Izinguquko Zokushisa:
– Ukusabela kwe-exothermic kuvame ukubangela ukwanda kokushisa kwemvelo, kuyilapho ukusabela kwe-endothermic kubangela ukwehla kokushisa.
3. I-Enthalpy:
– Ekusabeleni kwe-exothermic, i-enthalpy yemikhiqizo ingaphansi kwe-enthalpy yama-reactants. Ngokuphambene nalokho, ekusabeleni kwe-endothermic, i-enthalpy yemikhiqizo inkulu kune-enthalpy yama-reactants.
4. Isiqondiso Somcibisholo Wamandla Kumdwebo We-Enthalpy:
– Kumdwebo we-enthalpy wokusabela kwe-exothermic, umcibisholo wamandla uqondiswa phansi (okubonisa ukukhishwa kwamandla), kanti kukusabela kwe-endothermic, umcibisholo wamandla uqondiswa phezulu (okubonisa ukumuncwa kwamandla).
Ukusetshenziswa Empilweni Yansuku Zonke
Kokubili ukusabela kwe-exothermic kanye ne-endothermic kudlala indima ebalulekile ezicini ezahlukene zokuphila kanye nemboni. Nazi ezinye izibonelo:
Ukusabela Okungajwayelekile:
1. Ukufudumala Komhlaba:
– Ukushisa amafutha angaphansi komhlaba ukuze kukhiqizwe amandla kukhipha amandla amaningi okushisa emoyeni, okubangela ukufudumala komhlaba.
2. Imboni Nokukhiqiza Ugesi:
– Ukusabela kwe-exothermic njengokushiswa kwamalahle negesi yemvelo kusetshenziswa ezitshalweni zamandla ukukhiqiza amandla.
3. Ukuphepha:
– Amadivayisi amaningi okuphepha afana nomlilo wekamu noma iziqhumane asebenza ngesimiso sokusabela okubangelwa yi-exothermic.
Ukusabela Kwe-Endothermic:
1. Imishini Yokuqandisa:
– Amadivayisi amaningi okupholisa njengeqhwa elomile kanye namaphakethe okupholisa asebenza ngokusekelwe ekuphenduleni kwe-endothermic okumunca ukushisa okuvela endaweni ezungezile, ngaleyo ndlela kubangele ukupholisa.
2. Ukwakheka kwe-Ozone:
– Ukusabela okubalulekile kwe-endothermic emkhathini, njengokwakheka kwe-ozone, emunca imisebe ye-UV elangeni futhi ivikele umhlaba.
3. Inqubo Yezimboni:
– Ezinye izinqubo zezimboni, njengokucubungula insimbi nensimbi noma ukukhiqizwa kwamakhemikhali athile, zihilela ukusabela kwe-endothermic okudinga amandla amaningi.
Isiphetho
Ukusabela kwe-Exothermic kanye ne-endothermic kuyizinhlobo ezimbili eziyisisekelo zokusabela kwamakhemikhali ezidlala indima ebalulekile ezinqubweni ezahlukene zemvelo nezezimboni. Ukusabela kwe-Exothermic kukhulula amandla, kuyilapho ukusabela kwe-endothermic kumunca amandla. Umehluko omkhulu phakathi kwalokhu okubili usekutheni amandla aphathwa kanjani ngesikhathi sokusabela.
Ukuqonda ukusabela kwe-exothermic kanye ne-endothermic akubalulekile nje kuphela kososayensi nakonjiniyela, kodwa futhi kunezindlela ezisebenzayo ekuphileni kwethu kwansuku zonke. Kusukela emandleni esiwasebenzisa nsuku zonke kuya ezinqubweni zezinto eziphilayo ezenzeka emizimbeni yethu, lezi zinhlobo ezimbili zokusabela zikhona yonke indawo. Ngakho-ke, ukufunda ngokusabela kwe-exothermic kanye ne-endothermic kunikeza ukuqonda okujulile ngomhlaba wekhemistri kanye nezinqubo ezilawula impilo emhlabeni.
