The following rate constants were obtained in an experiment in which the decomposition of gaseous N2O; was studied as a function of temperature. The products were NO, and NO,.
Temperature (K) | |
3.5 x 10_i | 298 |
2.2 x 10"4 | 308 |
6.8 X IO-4 | 318 |
3.1 x 10 1 | 328 |
Determine Etfor this reaction in kj/mol.
Interpretation:
Concept introduction:
Rate of a reaction can be explained using either growth of products or reduction of reactants. Both give the same rate, but our concern is different.
Every reaction has activation energy. To overcome this energy sometimes we should provide energy from outside. But for some reactions, we do not have to supply energy. Ambient temperature is enough that reactions. Those reactions are called spontaneous reactions.
Answer to Problem 11.55PAE
Solution:
Given:
- Chemical reaction
Temperature/K | |
|
298 |
|
308 |
|
318 |
|
328 |
Explanation of Solution
The rate of the equation for the reaction can be written as follows.
- The only equation relating activation energy and rate constant is Arrhenius equation which is given below. The frequency factor doesn’t depend on the temperature.
It can be written as
Therefore, at two different temperatures at
When equation 1 is subtracted from equation 2,
Formula used:
Calculation:
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Chapter 11 Solutions
Chemistry for Engineering Students
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