Backward Reaction Rate Constant for 2nd Order Opposed by 1st Order Reaction Calculator

Formula Used:

\[ k2b' = kf' \times \frac{(A0 - xeq) \times (B0 - xeq)}{xeq} \]

Forward Reaction Rate Constant for 2nd Order:

m³/(mol·s)

Initial Concentration of Reactant A:

mol/m³

Initial Concentration of Reactant B:

mol/m³

Concentration of Reactant at Equilibrium:

mol/m³

Rate Constant for Backward Reaction:

m³/(mol·s)

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1. What is Backward Reaction Rate Constant for 2nd Order Opposed by 1st Order Reaction?

Definition: This calculator determines the rate constant for the backward reaction in a system where a second-order forward reaction is opposed by a first-order backward reaction.

Purpose: It helps chemists and chemical engineers analyze reaction kinetics and design chemical reactors.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ k2b' = kf' \times \frac{(A0 - xeq) \times (B0 - xeq)}{xeq} \]

Where:

\( k2b' \) — Rate constant for backward reaction (m³/(mol·s))
\( kf' \) — Forward reaction rate constant for 2nd order (m³/(mol·s))
\( A0 \) — Initial concentration of reactant A (mol/m³)
\( B0 \) — Initial concentration of reactant B (mol/m³)
\( xeq \) — Concentration of reactant at equilibrium (mol/m³)

Explanation: The formula relates the forward and backward rate constants through the equilibrium concentrations of the reactants.

3. Importance of Backward Reaction Rate Constant

Details: Knowing the backward rate constant is crucial for understanding reaction mechanisms, predicting reaction rates, and designing chemical processes.

4. Using the Calculator

Tips: Enter the forward rate constant, initial concentrations of both reactants, and the equilibrium concentration. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What are typical units for these rate constants?
A: For second-order reactions, units are typically m³/(mol·s). First-order reactions use s⁻¹.

Q2: How do I determine the equilibrium concentration?
A: Equilibrium concentration can be determined experimentally or calculated from thermodynamic data.

Q3: Can this be used for gas-phase reactions?
A: Yes, but concentrations should be in mol/m³ and pressure/temperature effects must be considered.

Q4: What if my reaction has different stoichiometry?
A: The formula would need adjustment to account for different stoichiometric coefficients.

Q5: How does temperature affect these calculations?
A: Rate constants are temperature-dependent (Arrhenius equation), so calculations are valid only at the temperature where the constants were measured.