Analytical Science and Technology (분석과학)

The Korean Society of Analytical Sciences (한국분석과학회)
권호 표지

A Study on the Measurement of Dissociation Constant of Organic Acid with FIA

FIA에 의한 유기산의 해리상수 측정에 관한 연구

  • Rhee, Jae-Seong (Korea Institute of Science & Technology, Advanced Analysis Center) ;
  • Park, Hyun-Mee (Korea Institute of Science & Technology, Advanced Analysis Center) ;
  • Kim, Hee-Jin (Korea Institute of Science & Technology, Advanced Analysis Center) ;
  • Lee, Kang-Bong (Korea Institute of Science & Technology, Advanced Analysis Center) ;
  • Dasgupta, Purnendu K. (Texas Tech. University, Department of Chemistry & Biochemistry)
  • 이재성 (한국과학기술연구원 특성분석센터) ;
  • 박현미 (한국과학기술연구원 특성분석센터) ;
  • 김희진 (한국과학기술연구원 특성분석센터) ;
  • 이강봉 (한국과학기술연구원 특성분석센터) ;
  • Received : 1994.03.17
  • Published : 1994.06.25
Download PDF
⟨ Previous Next ⟩

Abstract

The point of present study was focused on developing the method for the determination of dissociation constant by means of FIA conjunction with Diode Array Spectrphotometry or spectrophotometry along with small amount of Bromocresol Green(mg order) within short time. On the calculation with computer, the indicator with pK=7 has been shown the most sensitive reaction when little amount of base or acid has been added. The pKa of Bromothymol Blue and Bromocresol Green were measured as 7.31 and 4.82 respectively with spectrophotometry after activity correction by Kielland method (Reported value by Bishop, 7.30 and 4.79). The pKa of Bromocresol Green by FIA was obtained as 4.78 and was comparable with other values determined by other methods.

빠른 시간내에 적은 시료로(mg 단위) FIA와 Diode Array Spectrophotometry를 이용하여 해리상수를 구할 수 있는 방법을 개발하는 데 실험의 비중을 두었고, 그 대상으로 Bromo Cresol Green을 사용하였다. 소량의 산 염기를 가할 때 제일 sensitive한 발색반응을 보이는 지시약의 pK는 7.0임이 컴퓨터에 의해 계산되었다. Spectrophotometry를 이용한 Bromothylmol Blue와 Bromocresol Green은 Kielland 방법에 의한 Activity를 보정해 준 후 pKa가 각각 7.31과 4.82를 얻었다(Reported value by Bishop 7.30, 4.79). FIA에 의한 Bromocresol Green의 pKa값은 4.78을 얻어 다른 방법과 유사함을 알 수 있었다.

Keywords