Ideal solutions obey Raoult's Law.
Understanding Raoult's Law and Ideal Solutions
According to the provided reference, a solution that obeys Raoult's Law over the entire range of concentrations is called an ideal solution. Conversely, solutions that do not obey Raoult's Law across all concentrations are termed non-ideal solutions.
Characteristics of Ideal Solutions:
- They obey Raoult's Law.
- The interactions between the molecules of the components are similar.
- No heat is absorbed or released during mixing (zero enthalpy change).
- No volume change occurs upon mixing.
Raoult's Law Explained:
Raoult's Law states that the vapor pressure of a solvent above a solution is equal to the vapor pressure of the pure solvent at the same temperature, multiplied by the mole fraction of the solvent in the solution. In simpler terms, the presence of a solute lowers the vapor pressure of the solvent.
Examples (Note: Perfectly ideal solutions are rare):
While perfectly ideal solutions are uncommon in reality, some mixtures approximate ideal behavior:
- Benzene and Toluene
- Ethyl bromide and Ethyl iodide
- n-hexane and n-heptane
These mixtures exhibit molecular interactions that are quite similar, leading to behavior that closely follows Raoult's Law.
