Concentration of Product B in Set of Three Parallel Reactions Calculator

Concentration Formula:

\[ R_b = \frac{k_1}{k_1 + k_2 + k_3} \times A_0 \times (1 - e^{-(k_1 + k_2 + k_3)t}) \]

Reaction Rate Constant 1 (k₁):

1/s

Reaction Rate Constant 2 (k₂):

1/s

Rate Constant of Reaction 3 (k₃):

1/s

Initial Concentration of Reactant A (A₀):

mol/m³

Time (t):

Concentration of Reactant B (mol/m³):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Concentration of Product B in Parallel Reactions?

Definition: This calculator determines the concentration of product B formed in a set of three parallel first-order reactions from reactant A.

Purpose: It helps chemists and chemical engineers predict product distribution in parallel reaction systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ R_b = \frac{k_1}{k_1 + k_2 + k_3} \times A_0 \times (1 - e^{-(k_1 + k_2 + k_3)t}) \]

Where:

\( R_b \) — Concentration of product B (mol/m³)
\( k_1, k_2, k_3 \) — Rate constants for the parallel reactions (1/s)
\( A_0 \) — Initial concentration of reactant A (mol/m³)
\( t \) — Reaction time (s)

Explanation: The formula accounts for the competition between parallel reaction pathways and their relative rates.

3. Importance of the Calculation

Details: Understanding product distribution in parallel reactions is crucial for reaction optimization, selectivity control, and process design.

4. Using the Calculator

Tips: Enter all rate constants (k₁, k₂, k₃), initial concentration of A, and reaction time. All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What are parallel reactions?
A: Parallel reactions occur when a reactant can form different products through independent reaction pathways simultaneously.

Q2: How does the ratio of rate constants affect the product distribution?
A: The product ratio depends on the relative magnitudes of the rate constants. The product with the largest rate constant will dominate.

Q3: What units should I use for the rate constants?
A: The calculator expects first-order rate constants in reciprocal seconds (1/s).

Q4: Can this calculator be used for second-order reactions?
A: No, this formula is specific for first-order parallel reactions.

Q5: What does the exponential term represent?
A: It accounts for the depletion of reactant A over time as it converts to products B, C, and D.