The document discusses key concepts related to chemical reactions, including transition states, threshold energy, catalysts, bond dissociation energy, Lewis bases, and Lewis acids. It highlights the roles of electron donating and accepting species in chemical solutions. The repetition in the document may indicate emphasis on these essential chemical principles.

1. 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