The equilibrium liquid composition compared to the vapor composition in the case of an azeotropic mixture is the same.

Azeotropic mixtures are special types of liquid mixtures that have a constant boiling point and vapor composition. In other words, the liquid and vapor phases of an azeotropic mixture have the same composition at equilibrium. This behavior is due to the formation of a constant boiling point mixture, where the vapor phase and the liquid phase are in equilibrium and coexist at the same composition.

Explanation:

1. Azeotropic Mixtures:
- Azeotropic mixtures are formed when the components of a liquid mixture have a specific ratio that leads to a constant boiling point.
- The boiling point of an azeotropic mixture remains constant as long as the composition of the liquid and vapor phases remains constant.

2. Vapor-Liquid Equilibrium:
- Vapor-liquid equilibrium (VLE) is the state at which the vapor and liquid phases of a mixture are in equilibrium with each other.
- In a VLE system, the composition of the vapor and liquid phases can vary depending on the temperature and pressure.
- At equilibrium, the partial pressure of each component in the vapor phase is equal to the vapor pressure of that component at that temperature.
- The composition of the liquid phase at equilibrium is determined by the liquid-vapor equilibrium curve, which shows the relationship between the composition of the liquid and vapor phases at different temperatures.

3. Azeotropic Behavior:
- In the case of an azeotropic mixture, the liquid and vapor phases have the same composition at equilibrium.
- This means that the equilibrium liquid composition is equal to the equilibrium vapor composition.
- The constant boiling point of an azeotropic mixture is maintained because the liquid and vapor phases have the same composition, and any change in the composition will result in a change in the boiling point.

4. Importance of Azeotropic Mixtures:
- Azeotropic mixtures have practical applications in various industries, such as distillation processes, where the separation of components is required.
- Due to their constant boiling point, azeotropic mixtures cannot be separated by simple distillation.
- However, specialized techniques such as azeotropic distillation or extractive distillation can be employed to break the azeotrope and obtain pure components.

In conclusion, the equilibrium liquid composition in the case of an azeotropic mixture is the same as the equilibrium vapor composition. This behavior is due to the formation of a constant boiling point mixture, where the liquid and vapor phases have the same composition at equilibrium.