Understanding the Equilibrium Reaction
The equilibrium reaction under consideration is:
N2O4 ⇌ 2NO2
This reaction demonstrates the conversion of dinitrogen tetroxide (N2O4) into nitrogen dioxide (NO2).
Degree of Dissociation (α)
The degree of dissociation (α) refers to the fraction of the original N2O4 that has dissociated into NO2 at equilibrium.
Effect of Pressure on Equilibrium
- According to Le Chatelier's principle, increasing the pressure of a reaction at equilibrium favors the side with fewer moles of gas.
- In this case, the left side (N2O4) has 1 mole, while the right side (2NO2) has 2 moles. Thus, increasing the pressure will shift the equilibrium to the left, favoring the formation of N2O4.
Mathematical Relationship
- The degree of dissociation (α) can be expressed in relation to pressure (P).
- As pressure increases, the concentration of gases increases, which affects the degree of dissociation.
- Specifically, it has been found that α is inversely proportional to the square root of pressure (P): α ∝ 1/√P.
Intuitive Explanation
- At higher pressures, the system tends to favor the formation of fewer moles of gas (N2O4), thereby reducing the degree of dissociation.
- Conversely, at lower pressures, the equilibrium shifts towards more dissociation into NO2, leading to a higher α.
Conclusion
In summary, the degree of dissociation of N2O4 is inversely related to the square root of the pressure due to the principles governing gas behavior in equilibrium reactions. Understanding this relationship is crucial for manipulating reactions in industrial and laboratory settings.