Arrhenius Equation:
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The Arrhenius equation describes the temperature dependence of reaction rates. It's widely used in chemical kinetics and stability prediction to understand how temperature affects the rate of chemical reactions and degradation processes.
The calculator uses the Arrhenius equation:
Where:
Explanation: The equation shows that the rate constant increases exponentially with temperature and decreases with higher activation energy.
Details: Calculating the rate constant is essential for predicting reaction rates, determining shelf life of products, and understanding temperature-sensitive processes in pharmaceuticals, food science, and materials stability.
Tips: Enter the pre-exponential factor in 1/s, activation energy in J/mol, and temperature in Kelvin. All values must be positive numbers.
Q1: What are typical values for A and Ea?
A: A typically ranges from 1010 to 1013 1/s for simple reactions. Ea varies widely but often falls between 50-250 kJ/mol for many chemical reactions.
Q2: How does temperature affect the rate constant?
A: Generally, a 10°C increase in temperature approximately doubles the reaction rate for many systems (Q10 rule).
Q3: What's the difference between k and A?
A: A represents the maximum possible rate at infinite temperature, while k is the actual rate constant at a specific temperature.
Q4: Can this be used for biological systems?
A: Yes, but with caution as biological systems often have more complex temperature dependencies.
Q5: How accurate is the Arrhenius equation?
A: It works well for many simple reactions over moderate temperature ranges but may need modification for complex reactions or extreme conditions.