Te pH o ngā Waikawa Kaha me ngā Kawenga Kaha: Te Māramatanga Taketake me te Whakamahinga i te Ao
Nā te whanaketanga o te matū kua ārahi tātou ki te mārama ki ngā āhuatanga o ngā otinga mā te ariā o te pH. Ko ngā kāwai matua e rua o ngā otinga i runga i te tauine pH ko ngā waikawa me ngā kawakawa. Ka matapakihia e tēnei tuhinga te pH o ngā waikawa kaha me ngā kawakawa kaha, me pēhea te tatau i a rātou, me ō rātou whakamahinga i roto i te oranga o ia rā.
pH: Te Māramatanga Taketake
Ko te pH he ine i te kukū o ngā katote hauwai (H⁺) i roto i tētahi otinga. Ko te tauine pH kei waenga i te 0 ki te 14. Ko ngā otinga he pH iti iho i te 7 ka kiia he waikawa, ko ngā otinga he pH nui atu i te 7 ka kiia he taketake. Ko te pH o te 7 he kūpapa, pērā i te wai parakore.
He aha te hiranga o te pH?
He mea nui te ine i te pH i roto i ngā momo mara, tae atu ki te koiora, te matū, te ahuwhenua, me te hangarau kai. Hei tauira, he mea nui te pupuri i te pH pumau mō te haere tonu o ngā tukanga matū koiora i roto i te tinana tangata. I roto i te ahuwhenua, ka pā te pH oneone ki te wātea o ngā matūkai ki ngā tipu.
Waikawa Kaha
Ko te waikawa kaha he waikawa e whakakōkī katoa ana i roto i te wairewa. Ko te tikanga tēnei ka tukuna e ngā ngota waikawa katoa ngā katote hauwai (H⁺) ina rewa ki te wai. Ko ētahi tauira o ngā waikawa kaha ko te waikawa hauwaiora (HCl), te waikawa whanariki (H₂SO₄), me te waikawa hauota (HNO₃).
Tauira o te Tātaitanga pH o te Waikawa Kaha
Me kī he 0,1 M (molar) HCl tā tātou otinga. Nā te mea he waikawa kaha te HCl, ka tino wehea:
\[ \kuputuhi{HCl} \rightarrow \kuputuhi{H}^+ + \kuputuhi{Cl}^- \]
He rite te kukū o ngā iona H⁺ i roto i te otinga ki te kukū o te HCl, arā, 0,1 M. Ka taea te tatau i te pH mā te whakamahi i te whārite e whai ake nei:
\[ \kuputuhi{pH} = -\log[\kuputuhi{H}^+] \]
Nō reira, mō te otinga HCl,
\[ \text{pH} = -\log(0,1) = 1 \]
Pūtake Kaha
He rite ki ngā waikawa kaha, ko ngā turanga kaha he turanga e tino wehea ana i roto i te wairewa hei whakaputa i ngā katote hauwai (OH⁻). Ko ngā tauira o ngā turanga kaha ko te hauwai konutai (NaOH), te hauwai pāhare pākawa (KOH), me te hauwai konupūmā (Ca(OH)₂).
Tauira o te Tātaitanga pH o te Pūtake Kaha
Me kī he otinga NaOH tā tātou me te kukū o te 0,01 M. Ka wehea katoatia hoki te NaOH, he turanga kaha:
\[ \text{NaOH} \rightarrow \text{Na}^+ + \text{OH}^- \]
He rite te kukū o ngā iona OH⁻ ki te kukū o te NaOH, arā, 0,01 M. Hei tatau i te pH, me kimi tuatahi tātou i te pOH, nā te mea:
\[ \kuputuhi{pOH} = -\log[\kuputuhi{OH}^-] \]
Nō reira,
\[ \text{pOH} = -\log(0,01) = 2 \]
Nā te mea ko te pH me te pOH ka tāpirihia ki te 14,
\[ \kuputuhi{pH} = 14 – \kuputuhi{pOH} = 14 – 2 = 12 \]
Ngā Taupānga i roto i te Oranga o Ia Rā
1. Ahumahi
I roto i te umanga matū, he mea nui te mārama ki te pH o ngā waikawa kaha me ngā kawakawa kaha. Hei tauira, i roto i te hanga tongi, ka whakamahia pinepinetia ngā waikawa pēnei i te H₂SO₄. I roto i te maimoatanga wai para, ka whakamahia ngā kawakawa pēnei i te NaOH hei whakakore i te wai waikawa i mua i te tukunga ki te taiao.
2. Hauora
He mea nui te mārama ki te pH i roto i te rongoā. Hei tauira, ko te pH o te toto tangata he tata ki te 7,4. He tikanga nui te ine i te pH o te toto hei tautuhi i ētahi mate hauora, pērā i te waikawa, te alkalosis rānei.
3. Ahuwhenua
He mea nui te pH o te oneone hei whakatau i te wātea o ngā matūkai mō ngā tipu. He maha ngā wā ka whakamahia ngā waikawa me ngā kawakore kaha hei whakarerekē i te pH o te oneone kia rite ki te tipu o tētahi tipu.
4. Whare
He maha ngā wā kei roto i ngā hua horoi whare he kakano kaha pērā i te NaOH, he waikawa kaha rānei pērā i te HCl. He maha ngā wā ka whakamahia te NaOH i roto i ngā horoi paipa, ko te HCl ia e whakamahia ana i roto i ngā horoi wharepaku.
Te Tūranga o ngā Pūhui i roto i te Whakahaere i te pH
He wero te whakahaere i te pH i roto i te maha o ngā pūnaha koiora me ngā pūnaha matū. Ko te pūnaha ārai he otinga e kaha ana ki te tu atu i ngā huringa nui o te pH ahakoa he iti noa te waikawa kaha, te kawa rānei e tāpirihia ana. Ko ngā tauira o ngā pūnaha ārai taiao ko te pūnaha toto i roto i te tinana tangata.
Haumaru me te Whakahaere
He nui ngā tūponotanga mōrearea o ngā waikawa me ngā kawakore kaha. Ka taea e rātou te whakawera i te kiri, te kino hoki ki ngā kanohi me ētahi atu kiko. Nō reira, me whakamahi i ngā taputapu tiaki tika pērā i ngā karapu, ngā mōhiti kanohi, me te āpere matū hei whakahaere i ēnei matū kaha.
Whakamutunga
He mea nui te mārama ki te pH o ngā waikawa me ngā kawakawa kaha ki te whānuitanga o ngā kaupapa pūtaiao me ngā mahi whaihua. Mai i te whakaputa ahumahi ki te whakahaere koiora, he mea nui te whakahaere me te ine i te pH. Hei wāhanga o te hapori o te ao, me whakamahi tātou i tēnei mātauranga me te whakaaro nui hei whakatairanga i te hangarau me te tiaki i te taiao me te hauora o te tangata.
Mā te mōhio ki te tatau i te pH me te mārama ki ngā whakamahinga o ngā waikawa me ngā kawakawa kaha ka taea e tātou te wikitoria i ngā momo wero me te whakapai ake i te kounga o te oranga. Hei tangata e whai wāhi ana ki tēnei mara, me haere tonu ki te whakahōhonu me te whakapai ake i tō māramatanga ki ngā āhuatanga pH kia pai ake ai te whakamahinga.
