KCET2016ChemistryChemical Kinetics
The activation energy of a chemical reaction can be determined by,
Options
- Aevaluating rate constants at two different temperatures.
- BO changing the concentration of reactants.
- Cevaluating the concentration of reactants at two different temperatures.
- Devaluating rate constant at standard temperature,
Correct answer
A. evaluating rate constants at two different temperatures.
Step-by-step solution
Activation energy of a chemical reaction can be determined by measuring the values of rate constant at two differenttemperatures Let ( k₁ ) and ( k₂ ) are the rate constant for the reaction at two different temperature, that is, ( T₁ ) and ( T₂ ) respectively. ( k₁= A- E_ a 2.303 R T₁ (1) ) ( k₂= A- E_ a 2.303 R T₂ (2) ) Subtract Eq. (1) from Eq. (2), we get [ array l k₂- k₁= E_ a 2.303 R [ 1 T₁ - 1 T₂ ] k₂ k₁ = E_ a 2.303 R [ 1 T₁ - 1 T₂ ] k₂ k₁ = E_ a 2.303 R [ T₂-T₁ T₁ T₂ ] E_ a =2.303 R k₂ k₁ [ T₁ T₂ T₂-T₁ ] ar