ʻAkika-Base Brønsted-Lowry
Pendahuluan
He ʻāpana koʻikoʻi ke kumumanaʻo acid-base o ka kemika, e hāʻawi ana i kahi ʻike hohonu o nā ʻano hana kemika like ʻole a me nā waiwai o nā hui. ʻO kekahi kumumanaʻo kaulana loa a ʻae nui ʻia i ka kemika hou ʻo ia ke kumumanaʻo acid-base Brønsted-Lowry, i hāpai kūʻokoʻa ʻia e Johannes Nicolaus Brønsted o Denemaka lāua ʻo Thomas Martin Lowry o ʻEnelani i ka makahiki 1923. Hoʻohana kēia kumumanaʻo i ke kumumanaʻo o ka hoʻoili proton (hydrogen ion, H⁺) e wehewehe i nā waikawa a me nā kumu a hāʻawi i kahi hiʻohiʻona ākea a ʻoi aku ka maʻalahi ma mua o nā kumumanaʻo acid-base ʻē aʻe, e like me ke kumumanaʻo Arrhenius.
Nā Kumu o ke Kumumanaʻo Brønsted-Lowry
Wahi a ke kumumanaʻo Brønsted-Lowry, ʻo ka waikawa kahi ʻano e hiki ke hāʻawi i kahi proton (H⁺), ʻoiai ʻo ke kumu kahi ʻano e hiki ke ʻae a omo paha i kahi proton. ʻAe kēia manaʻo i kahi hoʻomaopopo maikaʻi ʻana i nā hopena e pili ana i nā protons a hiki ke hoʻopili ʻia i nā ʻano kemika like ʻole, ma nā hopena wai a me nā mea hoʻoheheʻe wai ʻole.
\[
\text{ʻakika} \rightarrow \text{cation (mea hāʻawi proton)} + \text{anion}
\]
\[
\text{Base} + \text{cation (mea lawe proton)} \rightarrow \text{ʻano i hoʻohui ʻia}
\]
Eia kekahi laʻana, ma ka hopena kuʻuna ma waena o ka waikawa hydrochloric (HCl) a me ka wai (H₂O):
\[
\text{HCl (ʻakika)} + \text{H₂O (kumu)} \rightarrow \text{H₃O⁺ (ʻiona hydronium)} + \text{Cl⁻ (ʻiona chloride)}
\]
Ma ke kaulike ma luna, hana ʻo HCl ma ke ʻano he waikawa Brønsted-Lowry no ka mea hāʻawi ia i kahi proton, ʻoiai ʻo H₂O e hana ma ke ʻano he kumu Brønsted-Lowry no ka mea ʻae ia i kahi proton.
ʻO ke kumumanaʻo o nā hui hui waikawa-kumu
ʻO kekahi o nā ikaika o ke kumumanaʻo Brønsted-Lowry ʻo ia kona hiki ke wehewehe i ke kumumanaʻo o nā hui waikawa-kumu hui. Ke hāʻawi kahi waikawa i kahi proton, lilo ia i kona kumu hui. I ka ʻaoʻao ʻē aʻe, ke ʻae kahi kumu i kahi proton, lilo ia i kona waikawa hui.
\[
\text{ʻAkika} + \text{Kumu} \rightarrow \text{ʻAkika Hoʻohui} + \text{Kumu Hoʻohui}
\]
Eia kekahi laʻana, ma ka hopena ma waena o ka waikawa acetic (CH₃COOH) a me ka wai (H₂O):
\[
\kikokikona{CH₃COOH} + \kikokikona{H₂O} \rightarrow \kikokikona{CH₃COO⁻} + \kikokikona{H₃O⁺}
\]
Ma kēia hopena, ʻo ka waikawa acetic (CH₃COOH) he waikawa Brønsted-Lowry e hāʻawi ana i kahi proton, a laila e lilo ana i ka ion acetate (CH₃COO⁻) ʻo ia kona kumu hui. Hana ka wai (H₂O) ma ke ʻano he kumu Brønsted-Lowry e ʻae ana i kahi proton, a lilo i ka ion hydronium (H₃O⁺) ʻo ia kona waikawa hui.
Ka ikaika o nā waikawa a me nā kumu
ʻO ke kumumanaʻo Brønsted-Lowry e ʻae pū i ka hoʻomaopopo ʻana i nā ikaika pili o nā waikawa a me nā kumu like ʻole. Ana ʻia ka ikaika o nā waikawa a me nā kumu e ko lākou ʻano e hāʻawi a ʻae paha i nā proton. E hāʻawi koke ka waikawa ikaika i kahi proton, e hana ana i kahi kumu conjugate nāwaliwali. I ka ʻaoʻao ʻē aʻe, e ʻae koke kahi kumu ikaika i kahi proton, e hana ana i kahi waikawa conjugate nāwaliwali.
Eia kekahi laʻana, ʻo ka waikawa hydrochloric (HCl) he waikawa ikaika e aneane piha loa i ka hopena wai e hoʻokuʻu i nā protons a hana i nā ion chloride (Cl⁻). No laila, he kumu conjugate nāwaliwali loa ʻo Cl⁻. I ka hoʻohālikelike ʻana, ʻo ka ammonia (NH₃) he kumu ikaika e ʻae ana i kahi proton e hana i ka ion ammonium (NH₄⁺), he waikawa conjugate nāwaliwali.
Nā Hoʻohana o ke Kumumanaʻo Brønsted-Lowry
He nui nā noi o ke kumumanaʻo waikawa-kumu Brønsted-Lowry i ke kemika, ma ka hale hana a me ka ʻoihana. ʻO kekahi mau noi koʻikoʻi o kēia kumumanaʻo:
1. Ke Hoʻomaopopo ʻana i nā Hana Hoʻohālikelike:
He nui nā hopena e pili ana i nā waikawa a me nā kumu he mau hopena kaulike. Kōkua ke kumumanaʻo Brønsted-Lowry e hoʻomaopopo pehea e hiki ai i nā loli o nā kūlana (e like me ka noʻonoʻo ʻana, ka mahana, a i ʻole ke kaomi) ke hoʻopilikia i ke kūlana o ke kaulike a me ka hopena o kahi hopena.
2. Hoʻonā Buffer:
ʻO ka buffer kahi hopena e mālama i kahi pH mau ʻoiai ke hoʻohui ʻia nā liʻiliʻi o ka waikawa a i ʻole ke kumu. Ma ka hoʻomaopopo ʻana i nā hui acid-base conjugate i loko o nā buffers, hiki iā mākou ke hoʻolālā i nā hopena buffer kūpono no nā noi biochemical, lapaʻau, a me nā ʻoihana.
3. Nā Hana ʻAkika-Kumu i ka Kemika Organika:
He nui nā hopena kemika organik e pili ana i ka hoʻoili proton. No ka laʻana, ka hopena esterification ma waena o ka waikawa carboxylic a me ka waiʻona a i ʻole nā hopena e pili ana i nā kumu e deprotonate i nā hui organik. Hāʻawi ke kumumanaʻo Brønsted-Lowry i kahi ʻōnaehana no ka hoʻomaopopo ʻana i nā ʻano hana o kēia mau hopena.
4. Ka Nānā ʻana i ka Titulation:
I ke kemika loiloi, ʻo ka titration acid-base kahi ʻenehana i hoʻohana ʻia e hoʻoholo ai i ka nui o nā hopena waikawa a i ʻole ke kumu. ʻO ka hoʻomaopopo ʻana i nā ikaika pili a me nā pilina o nā hui acid-base conjugate he mea nui ia i kēia ʻano hana.
Nā Palena o ke Kumumanaʻo Brønsted-Lowry
ʻOiai he mea pono loa ke kumumanaʻo Brønsted-Lowry, he mau palena kona. ʻO kekahi o kēia mau mea, ʻo ia kona hiki ʻole ke wehewehe i nā waikawa a me nā kumu me ka ʻole o ka hoʻokomo ʻana i nā proton. No ka laʻana, ʻaʻole hiki i ke kumumanaʻo ke wehewehe i ke ʻano o nā mea e like me ka alumini chloride (AlCl₃) a i ʻole boron trifluoride (BF₃), he mau waikawa akā ʻaʻohe proton.
No ka lanakila ʻana i kēia mau palena, ua hoʻomohala ʻia ke kumumanaʻo acid-base Lewis. Wahi a ke kumumanaʻo Lewis, he mea ʻae electron-pair ka waikawa, ʻoiai he mea hāʻawi electron-pair ke kumu. ʻOi aku ka laulā o kēia kumumanaʻo a hoʻokomo i ka wehewehe ʻana o Brønsted-Lowry no nā waikawa a me nā kumu a hoʻonui iā ia i nā ʻano i pili ʻole i nā protons.
Ka hopena
ʻO ke kumumanaʻo waikawa-kumu Brønsted-Lowry kahi alakaʻi koʻikoʻi no ka hoʻomaopopo ʻana i nā waiwai a me nā hopena o nā waikawa a me nā kumu. Ma ka wehewehe ʻana i nā waikawa ma ke ʻano he mau mea hāʻawi proton a me nā kumu ma ke ʻano he mau mea lawe proton, hāʻawi ke kumumanaʻo i kahi ʻōnaehana maʻalahi a piha hoʻi no ka nānā ʻana i nā hopena kemika. ʻOiai kona mau palena, ʻo ka hoʻomaopopo ʻana i ke kumumanaʻo Brønsted-Lowry he kahua koʻikoʻi ia ma nā wahi he nui o ke kemika, me nā hopena kaulike, nā hopena buffer, ke kemika organik, a me ka nānā ʻana i ka titration. No nā kūlana kahi i lawa ʻole ai kēia kumumanaʻo, hāʻawi ke kumumanaʻo Lewis i kahi koho ʻē aʻe ākea. No laila, ʻo ke kumumanaʻo Brønsted-Lowry ke kihi o ka hoʻonaʻauao kemika hou a me ka hoʻohana ʻana.
