Izisombululo Isinqandi: nokulungiselela kunye nokusetyenziswa

Isebenza - it izisombululo equlethe inkqubo kumthamo. Iinkqubo buffer ebizwa umxube apho ekwakhiweni iqulethe ratio oluninzi asidi amiselweyo buthathaka kwaye iityuwa zazo iziseko ukubabomelele iziseko ababuthathaka kunye iityuwa zazo kunye asidi kakhulu. izisombululo anjalo xi nokuzinzileyo H + ion kwi cala ngokuxuba sijike (amanzi) kunye nokongeza kubo isixa esithile asidi ukubabomelele, neziseko zazo.

izisombululo njengesikhuseli e amanzi iilwandle, izisombululo zomhlaba kunye eziphilayo. Le ndlela yokuqhuba imisebenzi ulawulo exhasa esebenzayo indlela eliphakathi kwi ixabiso elikhankanyiweyo kuyimfuneko isahlakalo ngempumelelo ngayo metabolic. izisombululo buffer zihlelwa zibe esidi esisiseko. Umzekelo ingaba kuqala inkqubo nezithinteli acetate, owesibini - Ammonium. Ukwahlula zebhodi yendalo neyenziweyo. Isisombululo buffer yendalo igazi equlethe hydrocarbonate, phosphate, iiproteins, ihemoglobin kunye nenkqubo buffer asidi. buffer ezingezizo abe buffer acetate, owakhiwa CH3COOH.

Iimpawu lwesakhiwo lwangaphakathi kunye indlela amanyathelo kweenkqubo yesidambisi siqwalasela umzekelo inkqubo ixeshana acetate: acetate acid / sodium acetate. Kulo zolwelo medium a kumacandelo inkqubo buffer ziphantsi dissociation electrolytic. Sodium acetate njengoko ityuwa ye asidi kunye nesiseko esomeleleyo dissociates ngokupheleleyo zibe ion. Ukubakho anions kwi umxube njengesikhuseli ixhomekeke kwindlela ekwakugquba ngayo ityuwa kuso kwaye izinga dissociation. Uyondelelwano lwee- H + ion kwinkqubo buffer endaweni leyo leevoti ngqo kwindlela ekwakugquba ngayo acid kuyo bomzimba kisekiyo kwisiqulatho zayo neetyuwa kwalo acid.

Ngoko ke, lo lwee- ion H + kwi buffer endaweni yokuyidibanisa esisiseko elijongene kisekiyo ngqo kwindlela ekwakugquba ngayo ityuwa kuso yaye bomzimba ngokomlinganiselo uyondelelwano lwee- kwisiseko.

Ukuziqhelisa laboratory, sebenzisa izisombululo buffer neenqobo ezaziwayo pH. Ngenxa yoko, ukulungiswa izisombululo buffer ikhutshwa phandle ngokusebenzisa izisombululo ye asidi kunye neetyuwa zayo isiseko esomeleleyo okanye isiseko buthathaka kunye netyuwa zayo esidi enamandla. Emva koko ngokuguqula umlinganiselo ubungakanani amacandelo, izisombululo buffer eyenziweyo kunye pH setpoint. Abanye bayazibuza indlela ukulungiselela sisombululo.

Umzekelo, ukuba kuyimfuneko ukulungiselela i buffer acetate kwi amaxabiso eziliqela pH. Ekuqaleni walungisa 5m nesisombululo acetate acid kunye sodium acetate. Kuba ukulungiselela isisombululo yokuqala athathe ml 50 ngalinye leekhomponenti. Kukhokelwa ifomula, uyazikhomba H + ion kwi isisombululo ngenxa.

Kuba isisombululo luphela Bathatha ml 80 yezisombululo acid kunye ml 20 kumxube wetyuwa walungisa ngaphambili. Kukho inani nemixube kwezisombululo ezahlukeneyo buffer esetyenziswa uhlalutyo lwekhemikhali kunye waselebhu.

Kuba iipropati zebhodi eqhelekileyo. Kwabo kuthetha komthamo - ukukwazi ukugcina rhoqo lwe uyondelelwano lwee- H + ion xa zafakwa kwi umthamo othile umxube buffer endaweni ye esidi enamandla okanye kwisiseko esiluqilima. Umzekelo, ukuba buffer acetate ukongeza imali encinci chloride acid, pH shift kwicala asidi lungenzeki, ekubeni chloride asidi kusabela yokubola wotshintshiselwano kunye ityuwa ye asidi. Reaction of a acid move ekwaziyo-pH kwicala asidi eyomeleleyo, yaye indawo ityuwa asidi cala. The degree of dissociation yokufumana isisombululo electrolyte ezibuthathaka ingqalelo ukwandisa unciphisa ukuya zero, kwaye shift pH kwenzeka.