Conductometry

Conductometry is a measurement of electrolytic conductivity to monitor a progress of chemical reaction. Conductometry has notable application in analytical chemistry, where conductometric titration is a standard technique.Principle of the conductometric titrations theory states that for dilutions that are infinite, ions act independently and in the process contribute toward conductance of the solution. The principle behind this theory states that anions and cations have different conductance values.

1. Electrochemical Methods of analysis Presented By, Prof.Vedanshu R.Malviya M.Pharm (Pharmaceutics) P. R.Pote Patil College of Pharmacy, Amravati.

2. Pharmaceutical Analysis It is divided into four types Electrochemical method Types of electrochemical methods 2

3. conductometry What is conductivity What is conductometry Conductometry and Titration Conductive Solution Strong Electrlytes Weak Electrolytes 3

4. Some imp terms Ohms Law Conductance Specific resistance Specific conductance Equivalent conductivity Molecular conductance : Effect of dilution 4

5. Instrumentation Conductivity cell Conductometer 5

6. Conductivity cell Made of pyrex or quartz and are fitted with two platinum electrodes . Should be placed in vessel containing water to maintain constant temperature . Determination of cell constant Types: 1 . Type-A – Low Conductance Measurement Cell 2 . Type-B- Conductivity cell for PPT type of cell 3 . Type-C- Dip Cell type Electrodes Conductivity Water 6

7. Principal of Conductometric Titration Reaction between anions and cations It is either increase or decrease 7

8. Types of Conductometric Titration The determination of end point of a titration by means of conductivity measurements are known as conductometric titrations . Acid-base titration Precipitation titration Replacement titration Redox (oxidation-reduction) titration Complexometric titration 8

9. Acid-base titration SA Vs SB SA Vs WB WA Vs SB WA Vs WB 9

10. Precipitation Titration [K + + Cl - ]+[Ag + +No 3 _ ] 10

11. Redox Titration 11 6 Fe 2+ +Cr 2 O 7 2- +14H + →6Fe 3+ +2Cr 3+ +7H 2 O

12. applications Determination of solubility of sparingly soluble material Kinetic studies Degree of dissociation of weaker electrolytes Basicity of organic acids Determination of concentration 12

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