Some reactions are described as parallel in that the reactant simultaneously forms different products with different rate constants. An example is
and
The activation energies are 45.3 kJ/mol for k1 and 69.8 kJ/mol for k2. If the rate constants are equal at 320 K, at what temperature will k1/k2 = 2.00?
Interpretation:
If the rate constants of given reactions are equal at
Concept introduction:
Arrhenius equation:
Arrhenius equation is a formula that represents the temperature dependence of reaction rates
The Arrhenius equation can be represented as follows
R represents the universal gas constant and it has the value of 8.314 J/K.mol
T represents the absolute temperature
If two rate constants at two temperture are known then the activation energy
Explanation of Solution
Some reactions are described as parallel in that the reactant simultaneously forms different products with different rate constants. Given example for such type of reactions are,
Activation energy for
If the rate constants of given reactions are equal at
Arrhenius equation is a formula that represents the temperature dependence of reaction rates
The Arrhenius equation can be represented as follows
The frequency factor A for each of the reaction can be determined as follows using the above equation,
Similarly frequency factor for reaction
Since
Assuming, the frequency factor is temperature independent and dividing
Take natural logarithm of both sides of the equation.
If the rate constants of given reactions are equal at
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Chapter 13 Solutions
Chemistry
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