... nh bng sau: Becher Dung dch N 20 ppm (ml) 0.1 0.3 0.6 0.9 1 .2 Nc ct ln 2. 9 2. 7 2. 4 2. 1 1.8 m pH = (ml) 2 2 2 Thuc th Nessler 0 .25 0 .25 0 .25 0 .25 0 .25 0 .25 12 18 24 N (g) Sau ú o quang bc súng ... tip): 2NH3 + H3BO3 = (NH4)2B4O7 + 5H2O (NH4)2B4O7 + 2HCl + 5H2O = 4H3BO3 + 2NH4Cl Hoc cú th s dng H2SO4 0.1N d, chun lng H2SO4 d bng dung dch NaOH 0.1N ( phng phỏp giỏn tip): 2NH3 + H2SO4 = ... m1 = 1,08g m2 = 1,08g mnc = 1,08g Th tớch dung dch Na2S2O3 tiờu tn: V1 = 4 ,2 ml V2 = 4,1 ml VB = 0,1 ml Ch s peroxide (mgH2O2/Kg) Vi mu th nht : (mgH2O2/Kg) Vi mu th hai : (mgH2O2/Kg) Vy ch s...