Tollens 'reagent yog cov tshuaj alkaline ntawm ammoniacal silver nitrate thiab yog siv los kuaj rau aldehydes . Silver ions nyob rau hauv lub xub ntiag ntawm hydroxide ions tawm los ntawm kev daws raws li xim av precipitate ntawm silver(I) oxide, Ag2O(s). Cov dej nag no yaj hauv aqueous ammonia, tsim cov diamminesilver(I) ion, [Ag(NH3)2+ .
Yuav ua li cas muab qhov ntsuas tus lej zoo?
Ib lub davhlau ya nyob twg α-hydroxy ketone muab qhov zoo Tollens 'kev sim vim tias Tollens 'reagent oxidizes α-hydroxy ketone rau ib qho aldehyde. Tollens 'reagent tov yog xim tsis muaj xim. ketone Ag + txo qis rau Ag0 uas feem ntau ua daim iav.
Lub hom phiaj ntawm kev xeem tus lej yog dab tsi?
Tollens 'test, tseem hu ua silver-mirror test, yog ib qho chaw kuaj zoo test siv los paub qhov txawv ntawm ib qho aldehyde thiab ketone. Nws siv qhov tseeb tias aldehydes tau nkag siab oxidized (saib oxidation), qhov ketones tsis yog.
Cov khoom kawg ntawm kev xeem tollen yog dab tsi?
Tollen's test yog ib qho tshuaj ntsuam xyuas siv los txiav txim siab txo cov suab thaj los ntawm cov piam thaj tsis txo qis. Nws tseem hu ua silver mirror test txij thaum free silver metalyog tsim los ntawm qhov kawg ntawm qhov kev ntsuam xyuas no. Nws kuj tseem pab kom muaj kev sib txawv ntawm aldehydes thiab ketones los ntawm kev txheeb xyuas cov organic zoo li niaj zaus.
Dab tsi yog tollens reagent nrog piv txwv?
Tollens reagent yog ibme me oxidizing tshuaj reagent uas yog siv nyob rau hauv lub Tollens 'test. Nws yog ib qho xim tsis muaj xim, yooj yim, thiab cov tshuaj aqueous uas muaj cov nyiaj ions ua haujlwm rau ammonia, tsim ib qho diaminesilver (I) complex [Ag(NH3) 2+. Tollens 'reagent yog npaj siv cov txheej txheem ob-kauj ruam.
