Qhov Tseem Ceeb Qhov txawv - Alkalinity vs Hardness
Txawm tias dej npog 71.1% ntawm lub ntiaj teb crust, dej txhua qhov chaw tsis zoo ib yam. Txawm li cas los xij, dej yog tib yam khoom tsis muaj zog uas tuaj yeem muaj nyob hauv tag nrho peb lub cev lub cev ib txwm muaj xws li dej, dej khov, lossis dej vapor. Qhov no yog vim qhov txawv ntawm qhov kub thiab txias. Raws li cov khoom sib xyaw uas yaj hauv nws, dej tuaj yeem sib txawv ntawm cov xim, saj lossis tshuaj lom neeg muaj pes tsawg leeg ntawm ib qho chaw mus rau lwm qhov. Piv txwv li, dej hiav txwv txawv heev ntawm cov qauv dej los ntawm lub qhov dej. Yog li ntawd, cov kev ntsuas dej tau raug qhia kom ntsuas cov dej zoo. Alkalinity thiab hardness yog cov tsis muaj qhov tseem ceeb heev uas yuav tsum tau kuaj ua ntej siv dej. Qhov sib txawv tseem ceeb ntawm alkalinity thiab hardness yog tias alkalinity ntsuas tag nrho cov hauv paus tam sim no hauv dej whereas hardness ntsuas tag nrho cov nyiaj (concentration) ntawm divalent ntsev.
Alkalinity yog dab tsi?
Alkalinity yog lub peev xwm ntawm dej kom nws cov pH ruaj khov. Nyob rau hauv lwm yam lus, alkalinity yog lub peev xwm ntawm dej kom neutralize acids. Qib ntawm alkalinity feem ntau yog nyob ntawm cov av lossis pob zeb uas nws hla. Alkalinity feem ntau tshwm sim vim muaj cov carbonate hom muaj nyob hauv dej. Nws muaj feem xyuam rau lub hauv paus ntawm cov dej. Alkalinity feem ntau yog los ntawm hydroxides lossis hauv paus. Carbonate hom pab txhawb rau alkalinity dua li lwm hom kab hauv paus vim tias muaj ntau hom carbonate muaj nyob hauv dej ib txwm muaj.
Alkalinity yog ib qho tseem ceeb parameter vim tias nws tuaj yeem cuam tshuam ncaj qha rau hauv dej. Qhov pH zoo tshaj plaws rau lub neej hauv dej kom ua haujlwm zoo yog 6.0-9.0 pH. Alkalinity pab tswj qhov pH ntawm cov dej hauv lub cev. Nws yog ntsuas nrog kev siv cov acid-base titration. Hauv qhov titration no, tus nqi ntawm cov kua qaub uas tuaj yeem nruab nrab ntawm cov qauv dej yog ntsuas. Cov carbonate hom yuav neutralize cov kua qaub thiab qhov kawg point yog tau thaum tag nrho cov carbonate hom tau noj.
Daim duab 01: Alkali Dej hauv Mono Lake
Dab tsi yog Hardness?
Dej hardness yog ntsuas qhov concentration ntawm tag nrho cov divalent ions tam sim no hauv dej. Piv txwv ntawm ib co divalent ions tam sim no nyob rau hauv dej yog calcium ion, magnesium ions, thiab Fe2+ ion. Txawm li cas los xij, calcium thiab magnesium yog qhov feem ntau ntawm cov dej hardness. Chav tsev rau hardness yog ppm ib CaCO3 sib npaug. Muaj ob hom dej hardness:
Temporary Hardness
Ib ntus hardness tshwm sim vim muaj calcium hydrogencarbonate (Ca (HCO 3) 2) thiab magnesium hydrogencarbonate (Mg (HCO) 3)2). Ob hom decompose thaum rhuab thiab CaCO3 los yog MgCO3 nag xob nag cua tshwm sim. Yog li ntawd, qhov tawv tawv ib ntus tuaj yeem raug tshem tawm los ntawm cov dej npau npau.
Nrhiav Hardness
Cov dej tsis tu ncua tshwm sim vim muaj calcium sulfate. Nws tsis tuaj yeem raug tshem tawm los ntawm cov dej npau npau.
Sodium carbonate tuaj yeem siv rau ob qho tib si ib ntus thiab ruaj khov tawv kom muag cov khib nyiab nyuaj. Sodium carbonate yog yaj hauv dej thiab muab cov carbonate ions txaus los cuam tshuam nrog calcium ions hauv dej. Qhov no pab ua kom cov dej tawv muag.
Qhov nyuaj ntawm cov dej tuaj yeem kwv yees tau yooj yim los ntawm EDTA titration. EDTA yuav khi nrog ob qho tib si calcium thiab magnesium ions; li no, nws tuaj yeem txiav txim siab tus nqi ntawm cov ions tam sim no.
Dab tsi yog qhov zoo sib xws ntawm Alkalinity thiab Hardness?
Cov ntsiab lus alkalinity thiab hardness feem ntau tsis meej pem vim muaj ntau qhov sib xws uas lawv sib koom. Ib qho zoo sib xws yog tias chav ntsuas ntsuas yog tib yam rau ob qho kev ntsuas, uas yog ppm (qhov ib lab) hauv CaCO3 sib npaug.
Lwm qhov zoo sib xws yog qhov hardness thiab alkalinity ntawm cov dej feem ntau yog los ntawm limestone lossis dolomite qhov chaw hauv qhov xwm txheej. Qhov no tshwm sim thaum cov dej dhau los ntawm cov pob zeb thiab cov zaub mov uas ua rau alkalinity thiab hardness., Thaum limestone thiab dolomite yaj hauv dej, calcium ions, magnesium ions, thiab carbonate hom sib xyaw nrog dej. Calcium thiab magnesium ions ua rau dej hardness thiab alkalinity tshwm sim vim muaj cov carbonate hom.
Dab tsi yog qhov txawv ntawm Alkalinity thiab Hardness?
Alkalinity vs Hardness |
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| Alkalinity yog lub peev xwm ntawm dej los tiv thaiv pH hloov uas tshwm sim vim acids. | Hardness yog ntsuas ntawm tag nrho cov nyiaj divalent ions tam sim no hauv dej. |
| Causative Species | |
| Alkalinity feem ntau yog tshwm sim los ntawm muaj cov carbonate hom. | Hardness yog tshwm sim los ntawm divalent ions xws li calcium, magnesium los yog hlau ions. |
| Kev txiav txim siab | |
| Alkalinity tuaj yeem txiav txim siab los ntawm acid-base titrations. | Hardness tuaj yeem txiav txim siab los ntawm EDTA titrations. |
| Reactions in Titrations | |
| Carbonate hom uas ua rau alkalinity tuaj yeem hnov mob nrog cov acids muaj zog nyob rau hauv lub xub ntiag ntawm phenolphthalein thiab methyl txiv kab ntxwv ntsuas kom muab cov xim hloov thaum tag nrho cov carbonate ions tau noj. | Calcium thiab magnesium ions uas ua rau tawv tawv tuaj yeem khi nrog EDTA thiab los ntawm kev nrhiav tus nqi ntawm EDTA, ib tus tuaj yeem pom qhov tawv ntawm cov qauv dej. |
Summary – Alkalinity vs Hardness
Alkalinity thiab hardness muaj nyob rau hauv cov dej ntuj hauv ntau qib. Cov no yog cov ntsuas siv los txiav txim siab cov dej zoo. Qhov sib txawv tseem ceeb ntawm alkalinity thiab hardness yog tias alkalinity ntsuas tag nrho cov hauv paus tam sim no hauv dej whereas hardness ntsuas tag nrho cov nyiaj (concentration) ntawm divalent ntsev.
Download PDF Version of Alkalinity vs Hardness
Koj tuaj yeem rub tawm PDF version ntawm kab lus no thiab siv nws rau offline hom phiaj raws li cov ntawv sau tseg. Thov download PDF version ntawm no Qhov txawv ntawm Alkalinity thiab Hardness.
