Ngā Tauira Pātai me te Kōrero mō te Pānga o te Tahunga Warowaihā
He mea noa te tahunga o ngā warowaihā i roto i ō tātou oranga o ia rā. Ko ngā warowaihā, he mea tito mai i ngā matū kei roto ngā ngota waro me te hauwai, koinei ngā wahie matua e whakamahia ana i roto i ngā momo rāngai, pērā i te kawe waka, te ahumahi, me ngā whare. Ahakoa he nui te pūngao e tukuna ana e te tahunga o ngā warowaihā, he maha ngā pānga o tēnei tukanga ki te taiao me te hauora o te tangata. Ka matapakihia e tēnei tuhinga ngā tauira me ngā pānga o te tahunga warowaihā.
Te Whakamāramatanga o ngā Hauwaiwaro
I roto i ngā āhuatanga matū, ko ngā warowaihā he matū waro e titoa ana i te hauwai me ngā ngota waro anake. Ko ngā tauira noa o ngā warowaihā ko te methane (CH₄), te ethane (C₂H₆), te propane (C₃H₈), me te butane (C₄H₁₀). Kei roto hoki i ngā warowaihā te hinu me ōna hua, pērā i te penehīni, te tīhiera, me te hau māori. Mā te tahunga o ngā warowaihā i te aroaro o te hāora nui ka puta he pūngao, he hauhā waro (CO₂), me te mamaoa wai (H₂O).
Te Tukanga Tahunga Hauwaiwaro
I te nuinga o te wā, ka taea te tuhi i te whārite tauhohenga mō te tahunga hauwaiwai penei:
CₓHᵧ + (x + \(\frac{y}{4}\)) O₂ → x CO₂ + \(\frac{y}{2}\) H₂O
Tauira mō te methane:
CH₄ + 2 O₂ → CO₂ + 2 H₂O
Te Pānga o te Tahunga Warowaihā
1. Ngā Tukunga Hau Kākāriki
Mā te tahunga o ngā warowaihā ka puta te hauhā waro (CO₂), he hau kati kōtuhi nui. Ka whai wāhi tēnei hau ki te pānga kati kōtuhi, ka mau te wera ki te āhuarangi, ka puta te mahana o te ao. Kātahi ka hua te mahana o te ao i te huringa āhuarangi, ka pā ki ngā āhuarangi tino kino, te rewa o ngā taupoki hukapapa o te pito tonga, me te pikinga o ngā taumata o te moana.
2. Te Parahanga o te Hau
Haunga te CO₂, ka tukuna hoki e te tahunga o ngā warowaihā ētahi atu poke pērā i te whanariki hauhā (SO₂), ngā waikura hauota (NOₓ), me ngā matūriki iti (PM). Ka puta mai i ēnei poke ngā raruraru hauora pērā i te mate huango, te mate pūkahukahu, me te mate ngakau, tae atu ki te pānga kino ki te taiao.
3. Ua Waikawa
Ka taea e te hauhā whanariki (SO₂) me ngā hauhā hauota (NOₓ) i puta mai i te tahunga o ngā warowaihā te tauhohe ki te mamaoa wai i te āhuarangi, ka hanga he waikawa whanariki (H₂SO₄) me te waikawa hauota (HNO₃). Ko te ua kei roto ēnei waikawa e mōhiotia ana ko te ua waikawa, ka taea te kino i ngā hua whenua, ngā whare, me ngā wai.
4. Te Hanganga o te Ozone Tropospheric (O₃)
Ka taea e ngā waikura hauota me ngā matū waro mimiti (VOC) i puta mai i te tahunga o ngā warowaihā te tauhohe ki te rā hei hanga i te ozone tropospheric. Ahakoa e tiaki ana te ozone stratospheric i a tātou mai i ngā hihi ultraviolet kino, he parahanga te ozone tropospheric ka taea te whakararu i te manawa me te kino i ngā hua whenua.
Ngā Pātai Tauira me te Kōrero
Anei ētahi tauira o ngā pātai me ngā kōrero e whakaahua ana i te pānga o te tahunga warowaihā i roto i te hohonutanga:
Pātai 1:
E mōhiotia ana ko te tahunga katoa o ngā mole propane e 2 (C₃H₈) ka puta he hauhā waro me te wai. E hia ngā mole o te CO₂ me te H₂O ka puta mai i tēnei tahunga? Whakaaturia ngā mahi hei whakaoti rapanga.
Kōrero:
Ko te whārite tauhohenga mō te tahunga o te propane ko:
C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O
Mai i te whārite tauhohenga i runga ake nei, e mōhio ana tātou ko te 1 mole o te propane (C₃H₈) ka whakaputa i te 3 mole o te CO₂ me te 4 mole o te H₂O. Nō reira, ki te tahuna e tātou te 2 mole o te propane:
– Ngā ngota CO₂ i hangaia = 2 mol C₃H₈ × 3 mol CO₂/mol C₃H₈ = 6 mol CO₂
– Ngā ngota H₂O i hangaia = 2 mol C₃H₈ × 4 mol H₂O/mol C₃H₈ = 8 mol H₂O
Nō reira, ko te tahunga o te 2 mole o te propane ka puta he 6 mole o te CO₂ me te 8 mole o te H₂O.
Pātai 2:
Mena e mōhiotia ana ka tukuna he 2,3 kg o te CO₂ i te tahunga o te 1 rita o te penehīni (hei tauira, te octane, C₈H₁₈), e hia te rahinga o te hau CO₂ ka puta i raro i ngā āhuatanga paerewa (0°C me te 1 atm), ki te whakaaro ko te mātotoru o te CO₂ he 1,98 kg/m³?
Otinga:
Tuatahi, ka tatauhia e tātou te nui o te CO₂ ka puta mēnā ka puta he 2,3 kg o te CO₂ i te 1 rita o te penehīni:
Papatipu o te CO₂ i hangaia = 2,3 kg
Te mātotoru o te CO₂ = 1,98 kg/m³
Rōrahi CO₂ = Papatipu CO₂ / Kiato CO₂
\[ \text{Rōrahi} \, CO2 = \frac{2.3 \, kg}{1.98 \, kg/m³} = 1.16 \, m³ \]
Heoi, me huri tātou i ngā waeine ki ngā rita mō te rōrahi:
1 m³ = 1000 rita
Nā, ko te rōrahi o te CO₂ i roto i ngā rita ko:
\[ 1.16 \, m³ \times 1000 \, rita/m³ = 1160 \, rita \]
Nō reira, e 1160 rita o te CO₂ ka puta i te 1 rita o te penehīni i raro i ngā āhuatanga paerewa.
Pātai 3:
He aha te mahi a te NOₓ i roto i te hanganga o te ozone tropospheric? Whakamāramahia te tikanga.
Kōrero:
Ko ngā waikura hauota (NOₓ) he parahanga matua nui mai i te tahunga warowaihā. Ko ō rātou wāhanga matua ko te hauota monoxide (NO) me te hauota hauhā (NO₂). Ko te tikanga o te hanganga o te ozone tropospheric he mā te tauhohenga matū e uru ana te NOₓ me ngā matū waro mimiti (VOC), penei:
1. NO₂ → NO + O (i te rā)
2. O + O₂ → O₃ (ōzone)
E whakaatu ana tēnei tauhohenga i te pakaru o te NO₂ ki te NO me ngā ngota hāora (O) mā te āwhina o te rā. Kātahi ka tauhohe ngā ngota hāora ki ngā ngota hāora (O₂) hei hanga i te ozone (O₃). Ko tēnei ozone, kei roto i te troposphere, he parahanga e kino ana ki te hauora o te tangata me ngā tipu.
Pātai 4:
Whakamāramahia me pēhea te whakaputanga o te ua waikawa i te tahunga o ngā hauwaiwaro, me tōna pānga ki te taiao?
Kōrero:
Ka puta te hauhā whanariki (SO₂) i te tahunga o ngā hauwaiwaro kei roto he whanariki. Kātahi ka tauhohe te hau SO₂ ki te hāora me te wai i te āhuarangi hei hanga waikawa whanariki (H₂SO₄):
\[ 2 SO₂ + O₂ → 2 SO₃ \]
\[ SO₃ + H₂O → H₂SO₄ \]
Hei tāpiritanga, ka puta mai hoki i te tahunga te hauota waikura (NOₓ) ka taea te tauhohe ki te wai hei hanga waikawa hauota (HNO₃):
\[ 2 NO₂ + H₂O → HNO₃ \]
Ko te ua e kawe ana i ngā waikawa whanariki me te hauota e mōhiotia ana ko te ua waikawa. Ko ōna pānga ki te taiao ko:
– Ngā tipu: Ka taea e te ua waikawa te kino i ngā rau, te aukati i te tipu, me te mate hoki o ngā tipu.
– Wai: Ka whakaheke i te pH o te wai, ka puta he waikawa ka mate ai ngā mea ora i roto i te wai.
– Ngā Whare: Ka waikura ki ngā rauemi hanga, inā koa ko ngā mea i hangaia ki te kōhatu kōhatu, ki te māpere rānei.
Mā te tirotiro i ngā tauira raruraru me ngā tikanga matū i runga ake nei, ka mārama ake tā tātou tirohanga ki ngā pānga taiao me te hauora o te tahunga warowaihā. He mea nui tēnei māramatanga mō te kimi i ngā huarahi kē atu e pai ake ana ki te taiao, me te whakatinana i ngā tikanga tahunga ma.
