Principle

The electric conductivity of aqueous electrolyte solutions is determined by the type and number of charge carriers at constant temperature. Characteristic changes in conductivity are connected with changes in the ionic composition of reacting systems. These can be used in the conductiometric titration as end point indicators.

Benefits

• Drop counter optimizes the experimental procedure
• Accurate results by conductivity probe with integrated sensor Pt 1000
• Simplified implementation: all pre-settings already prepared

Tasks

Using the Cobra4 system, measure the change in conductivity in the titrations of the following:

1. approximately 0.1 molar barium hydroxide solution with 0.1 molar sulphuric acid.
2. approximately 0.1 molar hydrochloric acid with 0.1 molar sodium hydroxide solution.
3. approximately 0.1 molar acetic acid with 0.1 molar sodium hydroxide solution.

Other samples can alternatively be set in advance for conductiometric determination of their concentration contents.

Learning objectives

• Electrolyte
• Electrical conductance
• Specific conductance
• Ion mobility
• Ion conductivity
• Conductometry
• Volumetry

Necessary accessories

• Precision balance 620g/0.001g

Software provided. Computer not included.