Principle

pH values can be measured with the aid of electrochemical measurements and proton-sensitive electrodes (e.g. glass electrodes). By combining a glass electrode with a reference electrode in one housing, a single-rod glass electrode, which is appropriate for acid-base titrations, is created. The titration curves allow an exact determination of the equivalence point in titrations of strong and weak acids and bases.

Benefits

• Drop counter optimizes the experimental procedure
• Simplified implementation: all pre-settings already prepared
• Extensive automation of the experiment allows concentration on the learning objectives

Tasks

1. Determine the titration curves of different neutralisation reactions.
2. Determine the titration curve of an ampholyte (glycine).
3. Determine the buffering capacity of various aqueous acetic acid/sodium acetate mixtures at different total concentrations.

Learning objectives

• Strong and weak electrolytes
• Hydrolysis
• Dissociation of water
• Amphoteric electrolytes
• Isoelectric point
• Law of mass action
• Indicators
• Glass electrode
• Activity coefficient
• Buffering capacity
• Henderson-Hasselbalch equation

Necessary accessories

• Precision balance 6200g/0.01g

Software provided. Computer not included.