What is your favourite chemical reaction and which chemicals are in it?

Question: What is your favourite chemical reaction and which chemicals are in it?
- Keywords:
  chemical,
  favourite,
  reaction
Asked by 583grte48 to Alice on 17 Mar 2016.
- Alice Harpole answered on 17 Mar 2016:
  
  I quite like the chemical reaction for respiration: glucose + oxygen -> carbon dioxide + water, as without it none of us would be alive. I also think it’s cool that such a simple formula can produce life.

Question: What is your favourite chemical reaction and which chemicals are in it?