Calculadora de Energia de Ativação
Calcule a energia de ativação de uma reação usando a equação de Arrhenius.
Activation Energy (Ea)
40,202 J/mol
Formula
## Arrhenius Equation for Activation Energy ### Formula **ln(k₂/k₁) = -(Ea/R) × (1/T₂ - 1/T₁)** Solving for Ea: **Ea = -R × ln(k₂/k₁) / (1/T₂ - 1/T₁)** Where: - **Ea** = activation energy (J/mol) - **R** = 8.314 J/(mol·K) - **k₁, k₂** = rate constants at temperatures T₁, T₂ - **T₁, T₂** = absolute temperatures (K)
Exemplo Resolvido
A reaction has k₁ = 0.001 at 300 K and k₂ = 0.01 at 350 K.
- 01Ea = -R × ln(k₂/k₁) / (1/T₂ - 1/T₁)
- 02ln(0.01/0.001) = ln(10) = 2.3026
- 031/350 - 1/300 = 0.002857 - 0.003333 = -0.000476
- 04Ea = -8.314 × 2.3026 / (-0.000476)
- 05Ea = 40,200 J/mol = 40.2 kJ/mol
Perguntas Frequentes
What is activation energy?
Activation energy is the minimum energy that reactant molecules need to start a reaction. Higher Ea means the reaction is slower at a given temperature.
How does a catalyst affect activation energy?
A catalyst provides an alternative reaction pathway with lower activation energy, speeding up the reaction without being consumed.
What is the Arrhenius equation?
k = A × e^(-Ea/RT), where A is the pre-exponential factor. It describes how the rate constant depends on temperature and activation energy.
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