Principle
Raoult's law states: The vapour pressure of an ideal solution is directly dependent on the vapour pressure of each chemical component and the mole fraction of the component present in the solution.
That's why the boiling point of a solution is always higher than that of the pure solvent. The dependence of the temperature difference (elevated boiling point) on the concentration of the solute can be determined using a suitabel apparatus.
Benefits
- Perfect as demonstration and student experiment
- Simplified implementation: all pre-settings already prepared
- Data logging via tablet possible.
- Flexible experimenting thanks to wireless data transmission
Tasks
- Measure the increase in the boiling point of water as a function of the concentration of table salt.
- Investigate the relationship between the increase in boiling point and the number of pellets.
- Determine the molar mass of the solute from the relationship between the increase in boiling point and the concentration.
What you can learn about
- Raoult's law
- Henry's law
- Ebullioscopic constants
- Chemical potential
- Gibbs-Helmholtz equation
- Concentration ratio
- Degree of dissociation
Necessary accessories
- Precision balance 620g/0.001g
Software included. Computer not provided.