Math Problem Statement

The activation energy for a decomposition reaction is 191 kJ/mol. The rate constant at 562 K is 3.52 × 10^-7 L/mol·s. What is the rate constant at 649 K?

Solution

The problem involves using the Arrhenius equation to determine the rate constant at a given temperature. Here’s a breakdown of the problem:

Given Information:

  1. Activation Energy, Ea=191kJ/molE_a = 191 \, \text{kJ/mol}
  2. Rate constant at 562 K, k1=3.52×107L/mol\cdotpsk_1 = 3.52 \times 10^{-7} \, \text{L/mol·s}
  3. Two temperatures: T1=562KT_1 = 562 \, \text{K} and T2=649KT_2 = 649 \, \text{K}
  4. The gas constant, R=8.3145J/mol\cdotpKR = 8.3145 \, \text{J/mol·K}

Formula:

We will use the Arrhenius equation in its logarithmic form for two temperatures: ln(k2k1)=EaR(1T11T2)\ln \left( \frac{k_2}{k_1} \right) = \frac{E_a}{R} \left( \frac{1}{T_1} - \frac{1}{T_2} \right) Where:

  • k1k_1 is the rate constant at T1T_1
  • k2k_2 is the rate constant at T2T_2
  • EaE_a is the activation energy
  • RR is the universal gas constant
  • T1T_1 and T2T_2 are the initial and final temperatures, respectively.

Selected Required Information:

The boxes that should be checked are:

  • Ea=191kJ/molE_a = 191 \, \text{kJ/mol} (This is required to calculate the rate constant using the Arrhenius equation)
  • k1=3.52×107L/mol\cdotpsk_1 = 3.52 \times 10^{-7} \, \text{L/mol·s} (This is the known rate constant at T1T_1)
  • T1=562KT_1 = 562 \, \text{K} and T2=649KT_2 = 649 \, \text{K} (These temperatures are needed to apply the Arrhenius equation)
  • R=8.3145J/mol\cdotpKR = 8.3145 \, \text{J/mol·K} (This is the gas constant in appropriate units)
  • The formula provided: ln(k2k1)=EaR(1T11T2)\ln \left( \frac{k_2}{k_1} \right) = \frac{E_a}{R} \left( \frac{1}{T_1} - \frac{1}{T_2} \right)

Would you like to proceed with the calculation of the rate constant at 649 K?

Relative Questions:

  1. How does the activation energy affect the rate constant in a reaction?
  2. Can the Arrhenius equation be used for all types of chemical reactions?
  3. Why is the rate constant dependent on temperature?
  4. What happens to the rate constant when the temperature is significantly increased?
  5. How is the gas constant RR related to the ideal gas law?

Tip:

Ensure that all units are consistent when applying the Arrhenius equation, particularly converting EaE_a from kJ/mol to J/mol.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Logarithms
Exponential Functions
Thermodynamics
Rate Laws

Formulas

Arrhenius Equation: ln(k2/k1) = (Ea/R) * (1/T1 - 1/T2)

Theorems

Arrhenius Law

Suitable Grade Level

College-level Chemistry or Advanced High School