AP EAMCET202022 Sep 2020Morning ShiftChemistryChemical KineticsActual
Decomposition of ethane, d [ C ₂ H ₆ ] d t =k [ C ₂ H ₆ ] proceeds through a complex mechanism, which includes 5 steps. The overall rate constant (k) can be expressed as k= k₁ k₂ k₃ k₂ k₅ . where k₁, k₂, k₃, k₄, k₅ are the rate constant of the 5 steps. If the activation energies of each of the steps respectively are E₁=1 E, E₂=2 E , E₃=3 E, E₄=4 E, E₅=5 E , where E=20 ~kJ / mol . Then find the overall activation ener
Options
- A6.67 ~kJ / mol
- B3.33 ~kJ / mol
- C20 ~kJ / mol
- D10 ~kJ / mol
Correct answer
C. 20 ~kJ / mol
Step-by-step solution
Given that, k= k₁ k₂ k₃ k₂ k₅ According to Arrhenius equation, k=A e^ - E_d R T aligned Overall E_a & = (E₁+E₂+E₃ ) (E₂+E₅ ) & =-[(20+40+60)-(40+100)] & =20 ~kJ / mol aligned Hence, the correct option is (3).