Nitrogen yog cov pa roj siv dav hauv kev tsim khoom, nrog rau ntau lub kaum tawm lwm cov sib xyaw ua ke. Nws tsis yog ib txwm hais kom thauj lossis khaws cov roj no rau hauv nws daim ntawv dawb huv, thiab qee zaum koj tsuas yog xav tau txiav txim siab nws muaj nyob rau hauv cov tshuaj. Rau qhov no, txheej txheem Kjeldahl siv. Tus txheej txheem Kjeldahl muaj qhov tseeb tias nitrogen, uas yog muaj nyob hauv cov kua tsis muaj kua, hloov mus rau hauv ammonium thaum lub sijhawm sib xyaw cov tshuaj tiv thaiv nrog sulfuric acid. Lub txiaj ntsig ammonia raug tso tawm dawb tom qab muaj kev tiv thaiv alkaline.
Cov Lus Qhia
Kauj ruam 1
Rau kev tsom xam, noj 4 ml ntawm cov ntshav, ntshav lossis ntshav dej, yaj nws nrog 8 ml ntawm dej distilled. Ntxiv 8 ml ntawm trichloroacetic acid rau tib lub khob haus dej. Do cov tshuaj kom zoo thiab lim.
Kauj ruam 2
Rau hauv lub raj tshuaj distillation, nchuav 5 ml ntawm cov kua lim, uas los ntawm lub neej ntawd yuav muaj 1 ml ntawm cov ntshav tshuaj. Ntxiv 1 ml ntawm reagent No. 2 muaj, taws cov roj ntawm cov nplaim hluav taws kom txog thaum pom cov pa dawb pom.
Kauj ruam 3
Tso cov qhov tso rau hauv cov kev uas nws qhov hauv qab tsuas yog me ntsis chwv lub nplaim taws. Cov txheej txheem sib txuas tau suav tias yog ua tiav thaum cov kua ua qhov ntxig daj lossis tsis muaj kob.
Kauj ruam 4
Teem lub raj pa dej kom txias. Txaus ib thiab ib nrab rau ob feeb. Txwv tsis pub, ib qho insoluble nag lossis daus yog tsim.
Kauj ruam 5
Tso dej hauv qab phab ntsa, muab yaug lub funnel nrog nws. Co kom txog thaum sib xyaw, sov taus lub hwj yog tias tsim nyog.
Kauj Ruam 6
Muab cov cuab yeej sib txuas, txuas nrog lub txais khoom. Tso 10 ml 0.01 N. tso rau hauv qhov tau txais. sulfuric acid daws. Ntxiv ib lossis ob tee rau ntawm methylroth. Tom qab sib tov tag nrho cov khoom xyaw, muab cov twj tso dej rau hauv lub dav hlau mus rau lub txais.
Kauj Ruam 7
Pib hla huab cua los ntawm kev npaj, ncuav 33% sodium hydroxide rau hauv qhov distillation, kom txog rau thaum cov kua hloov ntawm xim tsis muaj xim mus rau xim xiav tsaus lossis xim av tsaus. Qhov no qhia tau hais tias kev tiv thaiv alkaline.
Kauj ruam 8
Nres distillation tom qab kaum feeb. Kaw cov kais dej ntawm lub tshuab dej dav hlau, qhib lub ntsaws ntawm lub qhov txais, yaug cov sulfuric acid los ntawm qhov kawg ntawm lub raj tub yees. Hloov nrog lwm tus neeg txais nrog tib 0.01N ntim. sulfuric acid daws, ua ib ob distillation.
Kauj Ruam 9
Ntxiv cov dej qab ntsev rau thawj tus tau txais kom txog thaum lub teeb xim daj tau ntev li 30 feeb.
Kauj ruam 10
Xaus: 1 ml 0.01 N. sulfuric acid los yog sodium hydroxide sib raug rau 0.14 mg ntawm nitrogen.
Qhov sib txawv ntawm tus nqi ntawm sulfuric acid tso rau hauv lub txais thiab tus nqi ntawm sodium hydroxide coj thaum lub sij hawm titration, tsim tawm ntawm 0.14 mg, yog sib npaug nrog cov nqi ntawm cov pa nitrogen nyob rau hauv kev kuaj ntshav 1 ml ntawm cov ntshav. Txhawm rau qhia cov nqi ntawm nitrogen hauv milligram-feem pua, qhov tshwm sim yuav tsum khoo tawm nrog 100.
