1) Transition state 2) Threshold energy 3) Catalysts or Intermediates 4) bond Dissociation energy 5) Lewis bases or Elecron donating species or electron rich species 6) Lewis acids or Electron accepting species or electron poor species Solution 1) Transition state 2) Threshold energy 3) Catalysts or Intermediates 4) bond Dissociation energy 5) Lewis bases or Elecron donating species or electron rich species 6) Lewis acids or Electron accepting species or electron poor species.