Mocheso le phetoho ea mekhahlelo - mathata le litharollo
1. Ho latela kerafo, mocheso o monngoa ke metsi a 5-kg nakong ea ts'ebetso ea CD ke ofe? Mocheso o itseng oa metsi = 4,200 J/kg o C.
Tse tsejoang:
Boima (m) = 5 kg
Mocheso o itseng oa metsi (c) = 4200 J/kg o C
Mocheso oa pele (T 1 ) = 0 o C
Mocheso oa ho qetela (T 2 ) = 10 o C
Phetoho mochesong (ΔT) = 10 o C – 0 o C = 10 o C
Ho Batloa: Mocheso (Q)
Tharollo:
Q = mc ΔT = (5 kg)(4200 J/kg o C)(10 o C) = (5)(4200 J)(10) = (50)(4200 J) = 210,000 Joules
2. Mocheso o monngoang ke ligrama tse 20 tsa leqhoa nakong ea ts'ebetso ea AC ke ofe, haeba mocheso o itseng oa leqhoa e le 2100 J/kg o C 'me mocheso oa ho kopanya leqhoa e le 336,000 J/kg.
Tse tsejoang:
Boima ba leqhoa (m) = 200 grams = 200/1000 khilogremu = 0.2 khilogremu
Mocheso o itseng (c) = 2100 J/kg o C
Mocheso oa ho kopanya leqhoa (L F ) = 336,000 J/kg
Ho batloa: Mocheso o monngoang ke leqhoa nakong ea ts'ebetso ea AC
Tharollo:
Nakong ea ts'ebetso ea AB, mocheso o monngoa ke leqhoa ho fetola mocheso oa lona ho tloha ho -10 o C ho ea ho 0 o C.
Q = mc ΔT
Q = mocheso, m = boima ba leqhoa, c = mocheso o itseng oa leqhoa, ΔT = phetoho mochesong
Q 1 = mc ΔT = (0.2)(2100)(0-(-10) = (0.2)(2100)(10) = (2)(2100) = 4200 Joule
Nakong ea ts'ebetso ea BC, mocheso o monngoa ho qhibilihisa leqhoa lohle hore e be metsi. Ts'ebetsong ena e fetoha feela ka mekhahlelo 'me ha ho na phetoho mochesong. Leqhoa le mocheso oa metsi li lula li le 0 o C.
Mocheso o monngoa nakong ea ts'ebetso ea BC:
Q 2 = m L F = (0.2 kg)(336,000 J/kg) = 67,200 Joule
Mocheso o monngoa nakong ea ts'ebetso ea AC:
Q = Q 1 + Q 2 = 4200 Joule + 67,200 Joule = 71,400 Joule
3. Metsi a boima ba 2 kg a futhumatsoa, mme mocheso wa mouoane bakeng sa metsi = 2.27 x 10 6 J/kg, mocheso o itseng bakeng sa metsi = 4,200 J/kg o C mme kgatello ya sepakapaka ke 1 atm, mocheso o monngwa ke metsi ke ofe nakong ya tshebetso ya BC?
Tse tsejoang:
Boima (m) = 2 kg
Mocheso oa mouoane bakeng sa metsi (L V ) = 2.27 x 10 6 J/kg
Mocheso o itseng bakeng sa metsi (c) = 4,200 J/kg o C
Ho batloa: Mocheso o monngoa nakong ea ts'ebetso ea BC.
Tharollo:
Ha e ntse e sebetsa AB, mocheso o monngoa ho eketsa mocheso oa metsi ho tloha ho 60 o C ho isa ho 100 o C.
Q = m L V = (2 kg)(2.27 x 10 6 J/kg) = 4.54 x 10 6 Dijoule = 4540 x 10 3 Dijoule = 4540 kilo
4. Ho latela setshwantsho se ka tlase, haeba boima ba leqhoa e le digrama tse 500, mocheso o itseng ke 2100 J/kg o C mme mocheso o patehileng wa ho kopana ha leqhoa ke 336,000 J/kg. Fumana mocheso o hlokahalang tshebetsong P–Q–R.
Tse tsejoang:
Boima ba leqhoa (m) = 500 grams = 500/1000 kg = 0.5 kg
Mocheso o itseng bakeng sa leqhoa (c) = 2100 J/kg o C
Mocheso o patehileng oa ho kopanya (L F ) = 336,000 J/kg
Ho Batloa: Mocheso
Tharollo:
Ts'ebetso PQ = mocheso o monyelang ho phahamisa mocheso oa leqhoa ho tloha ho -4 o C ho isa ho 0 o C
Ts'ebetso QR = mocheso o monngoang ke leqhoa ho qhibilihisa leqhoa lohle ka metsing
Mocheso o monngoa nakong ea ts'ebetso PQ e baloang ho sebelisoa equation:
Q = mc ΔT
Q = mocheso, m = boima, c = mocheso o itseng oa leqhoa, ΔT = phetoho mochesong
Leqhoa le monyang mocheso nakong ea ts'ebetso PQ e baloang ho sebelisoa equation ena:
Q = (0.5 kg)(2100 J/kg o C)(0 o C-(-4 o C))
Q = (0.5 kg)(2100 J/kg o C)(0 o C + 4 o C)
Q = (0.5 kg)(2100 J/kg o C)(4 o C)
Q = (0.5)(2100 J)(4)
Q = 4200 Joule
Mocheso o monngoa nakong ea ts'ebetso ea QR e baloang ho sebelisoa equation ena:
Q = m L F
Q = (0.5 kg)(336,000 J/kg)
Q = (0.5)(336,000 J)
Q = 168,000 Joule
Mocheso o felletseng:
Q = Lijoule tse 4200 + Lijoule tse 168,000
Q = 172,200 Joule
Q = 172.2 kilograma ea Joule
Q = 172.2 kJ
5. Leqhoa le boima ba digrama tse 50 le futhumatswa ho tloha ho -5 o C ho ya metsing ka mocheso wa 60 o C. Haeba mocheso wa ho kopanya leqhoa e le 80 cal/gram, mocheso o itseng bakeng sa leqhoa ke 0.5 cal/gram o C, mocheso o itseng bakeng sa metsi ke 1 cal/gram o C, fumana mocheso o hlokahalang tshebetsong ya CD.
Tse tsejoang:
Boima ba leqhoa = boima ba metsi (m) = 50 grams 
Mocheso o patehileng oa ho kopanya leqhoa (LF ) = 80 cals/gram
Mocheso o itseng bakeng sa leqhoa (c leqhoa) = 0.5 cal/gram o C
Mocheso o itseng bakeng sa metsi (c metsi) = 1 cal/gram o C
Ho batloa: Ho hlokahala mocheso ho CD e sebetsang
Tharollo:
Mokhoeng oa A ho isa ho B, mocheso o sebelisoa ho phahamisa mocheso oa leqhoa ho tloha ho -5 o C ho ea ho 0 o C. Mocheso o baloa ho sebelisoa equation ena: Q = mc ΔT, moo Q = mocheso, m = boima ba leqhoa, c = mocheso o itseng bakeng sa leqhoa, ΔT = phetoho ea mocheso ho tloha ho -5 o C ho ea ho 0 o C.
Mokhoeng oa B ho isa ho C, mocheso o sebelisoa ho qhibilihisa leqhoa lohle hore e be metsi. Mokhoeng ona, mocheso ha o fetoloe. Mocheso o baloang ho sebelisoa equation ena: Q = m L F , moo Q = mocheso, m = boima ba leqhoa, L F = mocheso o patehileng oa ho kopana ha leqhoa.
Mokhoeng oa C ho isa ho D, mocheso o sebelisoa ho phahamisa mocheso oa metsi ho tloha ho 0 o C ho isa ho 60 o C. Mocheso o baloa ho sebelisoa equation ena: Q = mc ΔT, moo Q = mocheso, m = boima ba metsi, c = mocheso o itseng oa metsi, ΔT = phetoho mochesong ho tloha ho 0 o C ho isa ho 60 o C.
Mocheso o hlokahalang ho tloha ts'ebetsong ea C ho isa ho D:
Q = mc ΔT = (50 gram)(1 cal/gram o C)(60 o C-0 o C) = (50)(1)(60) cal = 3000 cal
6. Haeba boima ba leqhoa e le 1 kg, mocheso o itseng oa leqhoa ke 2100 J/kg o C, mocheso o patehileng oa ho kopanya leqhoa ke 336,000 J/kg mme mocheso o itseng oa metsi ke 4200 J/kg o C, ebe u fumana mocheso o hlokahalang ts'ebetsong ea PQR.
Tse tsejoang:
Boima ba leqhoa = 1 kg
Mocheso o patehileng oa ho kopana ha leqhoa (L F ) = 336,000 J/kg
Mocheso o itseng oa leqhoa (c leqhoa) = 2,100 J/kg o C
Mocheso o itseng oa metsi (c metsi) = 4,200 J/kg o C
Ho batloa: Ho hlokahala mocheso nakong ea ts'ebetso PQR
Tharollo:
Ts'ebetsong ea P ho isa ho Q, mocheso o sebelisoa ho phahamisa mocheso oa leqhoa ho tloha ho -5 o C ho isa ho 0 o C. Mocheso o baloa ho sebelisoa equation ena: Q = mc ΔT, moo Q = mocheso , m = boima ba leqhoa , c = mocheso o itseng oa leqhoa, ΔT = phetoho mochesong ho tloha ho -5 o C ho isa ho 0 o C.
Mocheso o hlokahalang ts'ebetsong P ho isa ho Q:
Q = mc ΔT = (1)(2100)(0-(-5)) = (2100)(5) = 10500 Dijoule
Ts'ebetsong ea Q ho isa ho R, mocheso o hlokahalang ho qhibilihisa leqhoa lohle ka metsing. Ts'ebetsong ena, mocheso ha o fetohe. Mocheso o baloa ho sebelisoa equation ena: Q = m L F , moo Q = mocheso , m = boima ba leqhoa , L F = mocheso o patehileng oa ho kopana ha leqhoa.
Mocheso o hlokahalang ts'ebetsong Q ho isa ho R:
Q = m L F = (1) (336,000) = 336,000 Joules
Mocheso o felletseng:
10,500 + 336,000 = 346,500 Joule
- Mocheso o patehileng ke eng?
- karabo: Mocheso o patehileng ke matla a mocheso a hlokahalang ho fetola mokhahlelo oa ntho ntle le ho fetola mocheso oa eona. O emela matla a hlokahalang ho roba kapa ho theha maqhama a limolek'hule nakong ea liphetoho tsa mokhahlelo.
- Ke hobane'ng ha mocheso o lula o tsitsitse nakong ea phetoho ea mohato?
- karabo: Nakong ea phetoho ea mohato, matla 'ohle a mocheso a fanoeng kapa a tlosoang a sebelisetsoa ho fetola mohato oa ntho. Matla ana a sebelisetsoa ho roba kapa ho theha maqhama a limolek'hule, eseng ho eketsa matla a kinetic kapa mocheso oa ntho.
- Phapang ke efe pakeng tsa mocheso o patehileng oa ho kopana le mocheso o patehileng oa mouoane?
- karabo: Mocheso o patehileng oa ho kopana o bolela matla a mocheso a hlokahalang ho fetola ntho ho tloha ho e tiileng ho ea ho e metsi (kapa ka tsela e fapaneng) sebakeng sa eona sa ho qhibiliha. Mocheso o patehileng oa ho fetoha mouoane o bolela matla a mocheso a hlokahalang ho fetola ntho ho tloha ho e metsi ho ea ho khase (kapa ka tsela e fapaneng) sebakeng sa eona sa ho belisa.
- Ke hobane'ng ha re ikutloa re bata ha re tsoa ka letamo la ho sesa letsatsing le nang le moea, leha mocheso oa moea o futhumetse?
- karabo: Ha metsi a ntse a fetoha mouoane letlalong la rona, a fetoha ka mokhoa o fetohang ho tloha mokelikeling ho ea mouoaneng. Ts'ebetso ena e hloka matla, a nkiloeng letlalong la rona ka mokhoa oa mocheso, a etsang hore letlalo la rona le ikutloe le pholile.
- Ke hobane'ng ha mouoane mochesong oa 100°C o le kotsi ho feta metsi a belang mochesong oa 100°C?
- karabo: Mouoane o na le matla a mangata ho feta metsi a belang hobane o monyetse mocheso o patehileng oa mouoane nakong ea phetoho ea mokhahlelo ho tloha metsing ho ea ho mouoane. Ha mouoane o kokobela letlalong, o ntša matla ana a eketsehileng, o baka ho chesa ho hoholo ho feta metsi a belang.
- Ho eketsa letsoai leqhoang ho fokotsa ntlha ea ho qhibiliha ha lona joang?
- karabo: Ho eketsa letsoai ho sitisa tekano pakeng tsa ho qhibiliha le ho hoama ha motsoako oa leqhoa le metsi. Sena se etsa hore leqhoa le lengata le qhibilihe mochesong o tlase ho feta tloaelo, e leng se fokotsang ntlha ea ho hoama ea motsoako ka katleho.
- Ke hobane'ng ha ho fufuleloa ho thusa ho pholisa 'mele letsatsing le chesang?
- karabo: Mofufutso, ha o tswa letlalong, o fetoha mouoane ho tloha mokelikeling ho ya ho kgase. Ts'ebetso ena ya mouoane e hloka matla, a nkwang letlalong, ka hona a le phodisa.
- Sublimation ke eng moelelong oa liphetoho tsa mohato?
- karabo: Sublimation ke phetoho e tobileng ea mohato ho tloha ho se tiileng ho ea ho khase ntle le ho feta mohatong oa metsi. Mohlala o tloaelehileng ke leqhoa le omileng (khabone e tiileng ea carbon dioxide) le fetohang ka ho toba khaseng ea carbon dioxide.
- Ke hobane'ng ha matla a mocheso a hlokahala ho qhibilihisa leqhoa leha mocheso o ntse o le ho 0°C?
- karabo: Matla a mocheso a sebediswa ho roba dibonto tsa dimolekhule tse tshwereng leqhoa sebopehong sa lona se tiileng. Hang ha dibonto tsena di robehile, leqhoa le fetohela mokgahlelong wa metsi, leha ho se na phetoho mochesong.
- Kgatelelo e ama ntlha e belang ya mokelikeli jwang?
- karabo: Ka kakaretso, ho eketsa kgatello ya kantle ho phahamisa ntlha ya ho bela ha mokelikeli, ha ho fokotsa kgatello ho fokotsa ntlha ya ho bela. Ke ka lebaka leo metsi a belang mochesong o ka tlase ho 100°C bophahamong bo phahameng, moo kgatello ya sepakapaka e leng tlase.
