You are comparing a reaction that produces a chemical change and one that prouduces a physical change. What evidence could you use to determine wich type of change is occurring?

Asuspension of yeast cells is being grown under anaerobic conditions such that glucose is degraded to ethanol and carbon dioxide. if one wishes to follow this process by monitoring the release of 14co2, at which positions in the glucose molecule would the 14c label need to be incorporated?