Item no.: P3030960
Principle
Carboxylic acids are potential electrolytes which exist in a weakly dissociated condition in aqueous solutions. The location of the dissociation equilibrium is quantitatively described by the Ka or pKa value which can be determined with potentiometric measurements.
Tasks
- Measure the alteration of the pH value during a titration of approximately 0.1 molar aqueous solutions of formic acid, acetic acid, monochloroacetic acid, propionic acid, butyric acid and lactic acid with a 0.1 molar sodium hydroxide solution at constant temperature using Cobra4 system.
- From the neutralisation curves read the pKa values of the acids and compare them.
What you can learn about
- True and potential electrolytes
- Strong and weak acids
- Law of mass action
- Henderson-Hasselbalch equation
- Dissociation constant and pKa value
- Substituent effects
- Potentiometry
Necessary accessories
- Precision balance 620g/0.001g
Software included. Computer not provided.