41. Therefore, the temperature for thermochemical sulfate reduction is much higher due to the activation energy required to reduce sulfate. 42. With E _ a \, the activation energy and \ Delta H _ r \, the reaction enthalpy change. 43. The sparks generated by striking steel against flint provide the activation energy to initiate combustion in this bunsen burner. 44. The activation energy , Ea, is used to characterize how easy or hard it is for the reaction to proceed. 45. For outer sphere redox reactions there cannot be such a reaction path, but nevertheless one does observe an activation energy . 46. Hemilabile ligands reduce the activation energy of these changes by readily undergoing partial and reversible displacement from the metal centre. 47. The relationship implies that the Gibbs free energy for proton dissociation is proportional to the activation energy for the catalytic step. 48. This observation is made reasonable assuming that the units must overcome an energy barrier by means of a thermal activation energy . 49. The apparent activation energy ( Q ) may be related to the thermally activated atomistic processes that occur during boundary movement. 50. The reaction is exothermic but has a high activation energy in the gas phase ( ~ 62 kcal / mol ).
