Journal of fhe Kor.wm ~hcmiLa/ .Socicr?
2m, vol.44, ,Vo. 4
Printed in tk Republic of Korea
Determination of the Crz0,2 Ion by a New Absorption Spectrometrk .Method Coupled with a Technique of Flow Injection Analysis
Hoon Hwang
Department of Chemism, Kangwon National Univemip. (%unclwrt 2LV-701, Koi-eu (Rcccivcd kbrwwy 28, 2000)
IiQ
11,s04
11,0 . ,
Rz DG
1 DT
PP
Fi4R.1. The systematic diagram of the FIA system for the determinwion of the Cr,0,2- ion in acid media. PP peristaltic pump. V sample injection valve, R, & Rz: reaction coils.
DG: clegassing line. DT. UV-VIS detector.
Tab/e2. The cfFccLof H.(k concentrationon the absorbanceot’
CIO(OZ)~([H$O~]=fixdat ().10M)
[H:OJ. M o.Io ().20 0.50 1.0 2.0
peakheight,cm 10.4 10.6 10.1 9.85 9.2
7uble3. Thedfcct of H*SO4concentrationon the absorbance of’CrW3j)~([I+.0~i=tixed at 0.20 M)
[H$O,I, M 0.010 0.020 0.10 0.20 0.50 peak height,cm 9.6 10.3 10.7 7.6 4,0
Table1.Mea.sud absmbancesof CrO(O~kover amnRC d’530nm and 650 run (IKzCIGI=4.03 < 10-’M)
wavelength, run 530 540 550 560 570 580 590 600 610 620 630 640 650
peakheight.cm S.1 8.8 9.4 9.7 10.0 10.2 10.3 10.3 10.2 10.() 9.95 9.9 9.85
Jourmd of the Korean C{zemical Society
4.OC
I
.6.IXIO -5,004 .4.000 -3.000 -2,LW Log [K2Cr20~
Fi,q. 2. Calibration curve constructed using standard solu-
tions of KXk07.
2000, V(d.44, No. 4
Table4.Absorbarmesof 1.0mii K,Cr,O,, Cr[O,), formed from 1.0 mM K,Cr,OJ(K) MM Cu2+ion,and 100 MM Ni2%n
imalytical wavelength, nm 403 run 590 run
speices I.0 MM 100 n>M 103 MM Cr(OJ2 forme from I00 mM 100 mNl
KzCr,O, CU2+ion fqj,. jon 1.0 MM K,Cr~O, CU2+ion Ni2+ion
absorburrce 0.120 0.002 0.056 ().262 ().009 0.021
ratio 1 0.017 0,47 I 0.034 0.080
olsia=~
LOL 3. Cotton, F. A,; Wilkinson, G., Basic Inorganic Chemi.~-
/v; John Wiley & Sons: New York, U.S.A., 1976; p 1. Kortum, G., Z Physik. Chew., 1936. Et33, 243, 395.
2. Kolthoff, I. M.; %ndcll, E. B.; Meehan, E. J.; Bruck- 4. Lingane, J. J.; Collat, J. W’.,AnaL (Xern., 1950, 22, ensteirr, S., Quantitative Chemical Ana!ysis: The Mac- 166.
millan company Toronto.(ln~ 19@ 4h. Ed., p. 1053.
2000,vol. 44, ,Vo.4
