Carbon dioxide is split to form oxygen gas and carbon compounds

I believe that the correct answer here is:

“in neither photosynthesis nor respiration”

This is because during photosynthesis, carbon dioxide is converted to glucose.

While during respiration, carbon dioxide is not split because it is one of the products of respiration hence it is rather created.

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.

ok whats the question if not i cannot you i need question and need a thing to answer