Buffer izixazululo: ukulungiswa nokusetshenziswa

Buffers - ke izixazululo equkethe kokubhafa uhlelo. Buffer izinhlelo ngokuthi inhlanganisela lapho Ukwakheka iqukethe eshiwo isilinganiso ambalwa acid ababuthakathaka nosawoti wabo lezisekelo eqinile noma elisekela ababuthakathaka nosawoti zabo acid eqinile. izixazululo ezinjalo lokuhlushwa nzile H + ion at kokungathathi hlangothi ekukhipheni kuphela (amanzi) kanye zizandise ethile acid eqinile noma izisekelo.

Buffer izixazululo ezisemanzini kwezilwandle, inhlabathi izixazululo futhi izinto eziphilayo. Lezi izinhlelo usebenze Izilawuli imisebenzi ukuthi ukusekela asebenzayo ukuphendula naphakathi kunani elicacisiwe ezidingekile nesenzakalo ngempumelelo ukusabela umzimba. Buffer izixazululo zihlukaniswa esidi eziyisisekelo. Isibonelo kungaba kuqala kube acetate sesikhashana uhlelo, kwesibili - ammonium. Hlukanisa isebenza zemvelo kanye yokufakelwa. Isixazululo zemvelo sesikhashana kuyigazi equkethe hydrocarbonate, phosphate, amaprotheni, i-hemoglobin kanye esidi sesikhashana sohlelo. isikhumbulo sesikhana Artificial kungenzeka sesikhashana acetate, ehlanganisa CH3COOH.

Izici isakhiwo sangaphakathi kanye mshini wezenzo izinhlelo sesikhashana sicabanga ngesibonelo acetate sesikhashana uhlelo: acetate acid / sodium acetate. Ngo medium aqueous wezinto sesikhashana uhlelo babhekana dissociation electrolytic. Sodium acetate njengoba usawoti a asidi kanye sizindza lesicinile dissociates ngokuphelele ku ion. Ukuba khona anions ingxube sesikhashana incike lokuhlushwa usawoti therein futhi degree yayo dissociation. I lokuhlushwa H + ion ohlelweni sesikhashana ngokuqondile wakhona lokuhlushwa acid kuwo futhi inhlukanozigaba kwekuqukethe nosawoti yaleli acid.

Ngakho, lo lokuhlushwa ion H + e sesikhashana eyisisekelo ngqo wakhona lokuhlushwa usawoti kuwo futhi inhlukanozigaba emakamu base.

Ngo-laboratory umkhuba, sebenzisa sesikhashana izixazululo amanani eyaziwayo pH. Ngakho, ukulungiswa sesikhashana izixazululo Kwenziwa ngokusebenzisa izixazululo of a asidi nosawoti yayo nge sizindza lesicinile noma isizinda ababuthakathaka nosawoti yayo nge oqinile acid. Khona-ke ngokushintsha isilinganiso ambalwa yezingxenye, sesikhashana izixazululo ekhiqizwa nge pH setpoint. Abanye bazibuza ukuthi kwenzeka kanjani ukulungela isixazululo.

Ngokwesibonelo, kubalulekile ukulungiselela i sesikhana acetate at amagugu eziningana pH. Ekuqaleni okulungiselelwe 5M ingxube acetate acid kanye sodium acetate. Ngokuba ukulungiswa ikhambi wokuqala ukuthatha 50 ml ngayinye izingxenye. Báqondiswa ifomula, lokuhlushwa H + ion in ikhambi okuholela.

Ngokuba ikhambi sesikhana olandelayo uthathe 80 ml ikhambi acid 20 ml kasawoti okulungiselelwe ngaphambili. Kunezindlela eziningana ukwakhiwa of sesikhashana izixazululo ahlukahlukene asetshenziswa ahlukahlukene okuhlaziya amakhemikhali futhi laboratory umkhuba.

Ukuze uthole ejwayelekile isebenza izakhiwo. Ukuze labo ngokuyinhloko lihlobene Ukugcina kumthamo - ikhono silondoloze ukuqinisela we lokuhlushwa H + ion lapho kungezwe ethile isixazululo sesikhana we eqinile acid noma sizindza lesicinile. Isibonelo, uma i sesikhana acetate ukwengeza inani elincane chloride acid, pH shift ohlangothini acid ingekho, kusukela chloride acid bazothini exchange noqhekeko nge usawoti a asidi. Ukusabela we acid hambisa eqinile uyakwazi pH eya ohlangothini acid, futhi zithathelwe indawo hlangothi ababuthakathaka usawoti acid. I degree of dissociation we electrolyte isixazululo ezibuthakathaka nge emakamu obandayo incipha zero, kanye shift pH kwenzeka.