39. He aha ka wai acidity a me ka alkalinity?
ʻO ka acidity o ka wai e pili ana i ka nui o nā mea i loko o ka wai e hiki ke hoʻopau i nā kumu ikaika. ʻEkolu ʻano mea ʻakika: nā ʻakika ikaika hiki ke hoʻokaʻawale loa i ka H+ (e like me HCl, H2SO4), nā ʻakika nāwaliwali e hoʻokaʻawale hapa i ka H+ (H2CO3, nā ʻakika organik), a me nā paʻakai i haku ʻia me nā waikawa ikaika a me nā kumu nāwaliwali (e like me NH4Cl, FeSO4). Ana ʻia ka ʻakika e ka titration me kahi hoʻonā kumu ikaika. ʻO ka ʻakika i ana ʻia me ka methyl ʻalani ma ke ʻano he hōʻailona i ka wā titration ua kapa ʻia ʻo methyl orange acidity, me ka acidity i hana ʻia e ke ʻano mua o ka ʻakika ikaika a me ke ʻano ʻekolu o ka paʻakai ʻakika ikaika; ka ʻakika i ana ʻia me ka phenolphthalein e like me ka mea i kapa ʻia ʻo phenolphthalein acidity, ʻo ia ka huina o nā ʻano acidity ʻekolu i luna, no laila ua kapa ʻia ʻo ia ka acidity holoʻokoʻa. ʻAʻole i loko o ka wai maoli ka ʻakika ikaika, akā aia nā carbonates a me nā bicarbonates e hana ai ka wai i ka alkaline. Ke loaʻa ka waikawa i loko o ka wai, ʻo ia ka mea pinepine ua haumia ka wai e ka waika.
ʻAʻole like me ka acidity, pili ka wai alkalinity i ka nui o nā mea i loko o ka wai e hiki ke hoʻokaʻawale i nā waikawa ikaika. ʻO nā mea i hoʻokumu ʻia i ka alkalinity, ʻo ia nā kumu ikaika (e like me NaOH, KOH) hiki ke hoʻokaʻawale loa i ka OH-, nā kumu nāwaliwali e hoʻokaʻawale hapa i ka OH- (e like me NH3, C6H5NH2), a me nā paʻakai i haku ʻia me nā kumu ikaika a me nā waikawa nāwaliwali (e like me Na2CO3, K3PO4, Na2S) a me nā ʻano ʻekolu ʻē aʻe. Hoʻohana ʻia ka alkalinity e ka titration me kahi ʻakika ikaika. ʻO ke ʻano alkalinity i ana ʻia me ka methyl alani ma ke ʻano he hōʻailona i ka wā titration ʻo ia ka huina o nā ʻano alkalinity ʻekolu i luna, i kapa ʻia ka alkalinity piha a i ʻole methyl orange alkalinity; ke ana ʻia ka alkalinity me ka phenolphthalein e like me ka mea i kapa ʻia ʻo phenolphthalein base. Degree, me ka alkalinity i hoʻokumu ʻia e ke ʻano mua o ke kumu ikaika a me kahi hapa o ka alkalinity i hana ʻia e ke ʻano ʻekolu o ka paʻakai alkali ikaika.
ʻO nā ʻano ana o ka acidity a me ka alkalinity, ʻo ia ka titration hōʻailona acid-base a me ka titration potentiometric, i hoʻololi pinepine ʻia i CaCO3 a ana ʻia i mg/L.
40. He aha ka pH waiwai o ka wai?
ʻO ka waiwai pH ka logarithm maikaʻi ʻole o ka hana hydrogen ion i loko o ka wai wai i ana ʻia, ʻo ia hoʻi, pH=-lgαH+. ʻO ia kekahi o nā hōʻailona maʻamau i hoʻohana ʻia i ke kaʻina hana hoʻomaʻemaʻe. Ma lalo o nā kūlana 25oC, inā he 7 ka pH waiwai, ua like nā hana o nā ion hydrogen a me nā ion hydroxide i loko o ka wai, a ʻo 10-7mol / L ka mea e pili ana. I kēia manawa, kū ʻole ka wai, a ʻo ka pH waiwai> 7 ʻo ia hoʻi he alkaline ka wai. , a me ka waiwai pH<7 means the water is acidic.
Hōʻike ka pH waiwai i ka acidity a me ka alkalinity o ka wai, akā ʻaʻole hiki ke kuhikuhi pololei i ka acidity a me ka alkalinity o ka wai. No ka laʻana, ʻo ka acidity o ka 0.1mol/L hydrochloric acid solution a me 0.1mol/L acetic acid solution he 100mmol/L hoʻi, akā ʻokoʻa loa ko lākou mau pH. ʻO ka pH waiwai o 0.1mol/L hydrochloric acid solution he 1, aʻo ka pH waiwai o 0.1 mol/L acetic acid solution he 2.9.
41. He aha nā ʻano hana e ana i ka waiwai pH?
I ka hana maoli ʻana, i mea e ʻike koke ai i ka hoʻololi ʻana i ka waiwai pH o ka wai ʻino e komo ana i ka hale mālama wai ʻino, ʻo ke ala maʻalahi ke ana ʻana me ka pepa hōʻike pH. No ka wai ʻōpala kala ʻole me ka pau ʻole o nā haumia, hiki ke hoʻohana ʻia nā ʻano colorimetric. I kēia manawa, ʻo ke ʻano hana maʻamau o koʻu ʻāina no ke ana ʻana i ka waiwai pH o ka maikaʻi o ka wai ʻo ke ʻano potentiometric (GB 6920–86 glass electrode method). ʻAʻole pili ʻia e ka waihoʻoluʻu, turbidity, colloidal substances, oxidants, a me nā mea hoʻohaʻahaʻa. Hiki iā ia ke ana i ka pH o ka wai maʻemaʻe. Hiki iā ia ke ana i ka waiwai pH o ka wai ʻōpala ʻoihana i haumia i nā degere like ʻole. He ala hoʻohana nui ʻia kēia no ke ana ʻana i ka waiwai pH ma ka hapa nui o nā mea kanu hoʻōla wai.
ʻO ke kumumanaʻo o ke ana potentiometric o ka waiwai pH ka loaʻa ʻana o ka hiki o ka electrode hōʻike, ʻo ia hoʻi, ka waiwai pH, ma ke ana ʻana i ka ʻokoʻa ma waena o kahi electrode aniani a me kahi electrode kuhikuhi me kahi hiki ke ʻike ʻia. Hoʻohana maʻamau ka electrode reference i kahi electrode calomel a i ʻole kahi electrode Ag-AgCl, me ka electrode calomel ka mea maʻamau. ʻO ke kumu o ka pH potentiometer he DC amplifier, e hoʻonui ana i ka hiki ke hana ʻia e ka electrode a hōʻike iā ia ma ke poʻo mika ma ke ʻano o nā helu a i ʻole nā kuhikuhi. Hoʻolako pinepine ʻia nā potentiometers me kahi mea hoʻoponopono wela e hoʻoponopono i ka hopena o ka mahana ma nā electrodes.
ʻO ke kumu hana o ka mika pH pūnaewele i hoʻohana ʻia i nā mea kanu hoʻomaʻemaʻe wai ʻo ia ke ʻano potentiometric, a ʻo ka mālama ʻana no ka hoʻohana ʻana he ʻano like ia me nā mika pH laboratory. Eia nō naʻe, no ka mea, hoʻomau mau ʻia nā electrodes i hoʻohana ʻia i loko o ka wai ʻino a i ʻole nā pahu aeration a me nā wahi ʻē aʻe i loaʻa ka nui o ka aila a i ʻole microorganisms no ka manawa lōʻihi, me ka koi ʻana i ka pH mika e hoʻolako ʻia me kahi mea hoʻomaʻemaʻe maʻemaʻe no nā electrodes, manual. koi ʻia ka hoʻomaʻemaʻe ma muli o nā kūlana maikaʻi o ka wai a me ka ʻike hana. ʻO ka maʻamau, hoʻomaʻemaʻe lima ʻia ka mika pH i hoʻohana ʻia i loko o ka wai inlet a i ʻole tank aeration i hoʻokahi manawa i ka pule, aʻo ka pH mika i hoʻohana ʻia i ka wai effluent hiki ke hoʻomaʻemaʻe lima ʻia i hoʻokahi mahina. No nā mika pH hiki ke ana i ka manawa like i ka mahana a me ka ORP a me nā mea ʻē aʻe, pono e mālama ʻia a mālama ʻia e like me ka mālama ʻana i koi ʻia no ka hana ana.
42. He aha nā mea e mālama ai no ke ana ʻana i ka waiwai pH?
⑴Pono ka potentiometer e maloʻo a pale i ka lepo, e hoʻohana mau ʻia no ka mālama ʻana, a e mālama ʻia ka maʻemaʻe o ka ʻāpana hoʻohui alakaʻi o ka electrode i mea e pale ai i nā kulu wai, lepo, ʻaila, a me nā mea ʻē aʻe mai ke komo ʻana. E hōʻoia i ka pae maikaʻi i ka wā e hoʻohana ai i ka mana AC. Pono nā potentiometers hiki ke ho'ohana i nā pila malo'o e ho'ololi mau i nā pila. I ka manawa like, pono e hoʻopili pinepine ʻia ka potentiometer a zeroed no ka calibration a me ka mālama ʻana. Ke hoʻopau pono ʻia, ʻaʻole hiki ke hoʻololi ʻia ka helu zero o ka potentiometer a me ka calibration a me nā mea hoʻonohonoho hoʻonohonoho i ka wā o ka hoʻāʻo.
⑵ʻO ka wai i hoʻohana ʻia no ka hoʻomākaukau ʻana i ka hopena buffer maʻamau a holoi i ka electrode ʻaʻole pono e loaʻa iā CO2, loaʻa ka waiwai pH ma waena o 6.7 a me 7.3, a me ka conductivity o lalo o 2 μs/cm. Hiki i ka wai i mālama ʻia me ka anion a me ka resin exchange cation ke hoʻokō i kēia koi ma hope o ka hoʻolapalapa ʻana a hoʻokuʻu ʻia. Pono e hoʻopaʻa ʻia a mālama ʻia i loko o ka hue aniani paʻa a i ʻole ka hue polyethylene i hoʻomākaukau ʻia i loko o ka friji ma 4oC e hoʻolōʻihi i ke ola lawelawe. Inā mālama ʻia ma ka lewa ākea a i ʻole ma ka lumi wela, ʻaʻole hiki ke ola o ka lawelawe ma mua o 1 mau mahina, ʻaʻole hiki ke hoʻihoʻi ʻia ka buffer i hoʻohana ʻia i ka hue mālama no ka hoʻohana hou ʻana.
⑶ Ma mua o ke ana ʻana, e nānā mua inā he mea maʻamau ka mea hana, electrode, a me ka buffer maʻamau. A pono e calibrated mau ka pH meter. ʻO ka maʻamau ka hoʻololi ʻana i hoʻokahi hapaha a i ʻole hapalua makahiki, a hoʻohana ʻia ke ʻano calibration ʻelua no ka calibration. ʻO ia hoʻi, e like me ka pae waiwai pH o ka laʻana e hoʻāʻo ʻia, koho ʻia ʻelua mau mea hoʻonā maʻamau e pili kokoke ana iā ia. ʻO ka maʻamau, ʻoi aku ka liʻiliʻi o ka ʻokoʻa pH ma waena o nā haʻina buffer ʻelua. ʻO ka ʻokoʻa ma waena o ka hopena hōʻike o ka potentiometer a me ka waiwai pH maʻamau o ka hopena buffer maʻamau ʻelua ʻaʻole pono e ʻoi aku ma mua o 0.1 pH unit. Inā ʻoi aku ka hewa ma mua o ka ʻāpana pH 0.1, pono ke hoʻohana ʻia ke kolu o ka hopena buffer maʻamau no ka hoʻāʻo ʻana. Inā emi ka hewa ma mua o 0.1 pH i kēia manawa, aia paha ka pilikia me ka hoʻonā paʻa lua. Inā ʻoi aku ka nui o ka hewa ma mua o 0.1 pH unit, aia kekahi hewa i ka electrode a pono e hoʻoponopono ʻia ka electrode me kahi mea hou.
⑷I ka wā e hoʻololi ai i ka pale maʻamau a i ʻole ka laʻana, pono e holoi ʻia ka electrode me ka wai i hoʻoheheʻe ʻia, a ʻo ka wai i hoʻopili ʻia i ka electrode pono e hoʻopili ʻia me ka pepa kānana, a laila holoi ʻia me ka hopena e ana ʻia e hoʻopau i ka mana like. He mea nui kēia no ka hoʻohana ʻana i nā pale palupalu. He mea koʻikoʻi kēia i ka hoʻohana ʻana i nā hāʻina. Ke ana ʻana i ka waiwai pH, pono e hoʻoulu ʻia ka hopena wai e hoʻohālikelike i ka hopena a loaʻa i ka equilibrium electrochemical. I ka heluhelu ʻana, pono e hoʻōki i ka hoʻoulu ʻana a ʻae ʻia e kū no kekahi manawa i mea e paʻa ai ka heluhelu ʻana.
⑸ I ke ana ana, e holoi mua i na electrodes elua me ka wai, a laila holoi me ka wai sample, a laila e hookomo i na electrodes i loko o ka beaker liʻiliʻi i loko o ka wai laʻana, lulu i ka beaker me kou mau lima e hana i ka wai hoʻohālike like, a kākau i ka pH ma hope o ka paʻa ʻana o ka heluhelu ʻana.
Ka manawa hoʻouna: Oct-26-2023
