Meeting 9 : Complexometric Methods - PowerPoint PPT Presentation

torie
meeting 9 complexometric methods n.
Skip this Video
Loading SlideShow in 5 Seconds..
Meeting 9 : Complexometric Methods PowerPoint Presentation
Download Presentation
Meeting 9 : Complexometric Methods

play fullscreen
1 / 14
Download Presentation
Meeting 9 : Complexometric Methods
144 Views
Download Presentation

Meeting 9 : Complexometric Methods

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Meeting 9 : Complexometric Methods

  2. Complexometry volumetric • Volumetric analysis that involve the complex formation of titrate and titrant reaction in aquous media

  3. Examples: • Reaction between silver ion with cyanide ion: Ag+ + 2CN- Ag(CN)2- • Reaction between calsiumion with EDTA • Ca2+ + EDTA Ca-EDTA + 2H+

  4. Complex formation • Centre atom/ion : metal ions • Ligand • Electron pairs donor • Electron pairs acceptor • Coordination number

  5. Examples

  6. The most popular titration • Metal ions + EDTA (Ethylene diamine tetra acetic acid)

  7. REACTION: • Use: EDTA salt (sodium)  easy to solve • Trilon B, Complexone III, atauTitriplex III.

  8. Cu2+

  9. Simple expression: • Ca 2+ + H 4Y == CaY2- + 4 H+ • Ca 2+ + H2Y 2-== CaY2- + 2 H+ • Ca 2+ + HY 3-== CaY2- + H+ • Ca 2+ + Y 4- == CaY2- Always release hydrogen ion  need buffer

  10. indicators: • M + In == Min • MIn + EDTA == M-EDTA + In

  11. Some indicators • Murexide Determination of Ca(II)  pH = 11 Ca + Mur == Ca-Mur red • Ca-Mur + EDTA == Ca-EDTA + Mur red blue-violet

  12. Some Indicators • EBT (Eriochrom Black T): Determination of Mg(II)  pH = 10 Mg + EBT == Mg-EBT red • Ca-EBT + EDTA == Mg-EDTA + EBT red blue

  13. Curve of Titration: 50 mL 0,0100 M Ca2+is titrated with 0,0100 M EDTA ( pH 10 )

  14. Application: • Determine water total hardness (Kesadahan total): • Alkali metals : Mg(II) + Ca(II) • Total Hardness: mg of CaCO3per liter • Soft water : TD< 60 mg/L