Title: Investigation of Heterogeneous Equilibrium using Phenol and Water
Heterogeneous equilibrium refers to a chemical equilibrium involving reactants and products in different phases. In this experiment, the aim is to investigate the heterogeneous equilibrium between phenol and water. Phenol is a weak acid that partially dissociates in water, forming phenoxide ions and hydronium ions. The equilibrium between these species will be studied using a glass tube thermometer storer and a beaker.
2. Materials and Methods:
- Phenol (C6H6O)
- Distilled water (H2O)
- Glass tube thermometer storer
- Stirring rod
1. Prepare a 10% phenol solution by adding 10 mL of phenol to 90 mL of distilled water in a beaker.
2. Place the glass tube thermometer storer in the beaker, ensuring that it is fully submerged in the solution.
3. Insert a thermometer into the glass tube thermometer storer and record the initial temperature.
4. Stir the solution gently using a stirring rod.
5. Allow the system to reach equilibrium, monitoring the temperature periodically.
6. Record the final temperature once equilibrium is achieved.
3. Results and Discussion:
During the experiment, the temperature of the system is monitored to determine if any changes occur, indicating a shift in the equilibrium. The initial temperature represents the conditions before the system reaches equilibrium, while the final temperature represents the equilibrium state.
The equilibrium between phenol and water can be represented by the following equation:
C6H6O (phenol) + H2O ⇌ C6H5O- (phenoxide ion) + H3O+ (hydronium ion)
If the temperature increases during the experiment, it suggests that the forward reaction is favored, indicating an increase in the concentration of phenoxide ions and hydronium ions. Conversely, if the temperature decreases, the reverse reaction is favored, suggesting a decrease in the concentration of phenoxide ions and hydronium ions.
The observed temperature change will depend on the relative concentrations of the reactants and products at equilibrium. If the phenol concentration is high, the forward reaction will be favored, resulting in an increase in temperature. On the other hand, if the phenoxide ion and hydronium ion concentrations are high, the reverse reaction will be favored, leading to a decrease in temperature.
The investigation of the heterogeneous equilibrium between phenol and water using a glass tube thermometer storer and a beaker provides insights into the temperature changes associated with the equilibrium. By monitoring the temperature, it is possible to determine the direction in which the equilibrium shifts and infer the relative concentrations of the reactants and products at equilibrium. This experiment serves as a valuable tool for understanding the principles of heterogeneous equilibrium and its application in chemical systems.