How To Calculate Partial Pressure In Chemical Equilibrium

Partial Pressure Equation:

\[ P_i = K_p \times \left( \frac{P_{\text{total}}}{K_c} \right)^{\Delta n} \]

Equilibrium Constant (K_p):

dimensionless

Total Pressure (P_total):

Equilibrium Constant (K_c):

dimensionless

Change in Moles (Δn):

dimensionless

Partial Pressure (P_i):

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1. What Is Partial Pressure In Chemical Equilibrium?

Partial pressure in chemical equilibrium refers to the pressure exerted by an individual gas in a mixture of gases. It plays a crucial role in determining the position of equilibrium in gas-phase reactions and is calculated using equilibrium constants and total system pressure.

2. How Does The Calculator Work?

The calculator uses the partial pressure equation:

\[ P_i = K_p \times \left( \frac{P_{\text{total}}}{K_c} \right)^{\Delta n} \]

Where:

\( P_i \) — Partial pressure of the component (Pa)
\( K_p \) — Equilibrium constant in terms of partial pressures (dimensionless)
\( P_{\text{total}} \) — Total pressure of the system (Pa)
\( K_c \) — Equilibrium constant in terms of concentrations (dimensionless)
\( \Delta n \) — Change in number of moles in the reaction (dimensionless)

Explanation: This equation relates the partial pressure of a gas component to the total pressure and equilibrium constants, accounting for the stoichiometric changes in the reaction.

3. Importance Of Partial Pressure Calculation

Details: Calculating partial pressures is essential for predicting reaction directions, determining equilibrium positions, and understanding how pressure changes affect chemical systems in industrial processes and environmental chemistry.

4. Using The Calculator

Tips: Enter all equilibrium constants and pressure values. Ensure K_c is not zero and total pressure is non-negative. The calculator will compute the partial pressure of the specified component.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between K_p and K_c?
A: K_p is the equilibrium constant expressed in partial pressures, while K_c uses concentrations. They are related through the ideal gas law and Δn.

Q2: When is this equation most applicable?
A: This approach is particularly useful for gas-phase reactions at equilibrium where pressure measurements are available.

Q3: How does temperature affect partial pressure calculations?
A: Temperature affects the values of K_p and K_c, but the fundamental relationship between partial pressure and total pressure remains valid.

Q4: Can this be used for ideal gas mixtures only?
A: The equation assumes ideal gas behavior. For real gases at high pressures, corrections may be needed.

Q5: What if Δn = 0?
A: When Δn = 0, the equation simplifies to P_i = K_p since (P_total/K_c)^0 = 1.