Final answer:
The purpose of the soda lime in a xenon administration unit is to absorb carbon dioxide from exhaled air in anesthesia systems, preventing rebreathing of CO2.
Step-by-step explanation:
The purpose of the soda lime in a xenon administration unit is to absorb carbon dioxide (CO2). Soda lime is a mixture of chemicals, primarily calcium hydroxide, that reacts with the CO2 exhaled by a patient to prevent rebreathing of the same gas. This is particularly important in closed or semi-closed circuit anesthesia systems where the xenon gas, used as an anesthetic, is recirculated. Soda lime effectively removes CO2 by converting it into calcium carbonate, ensuring that the gas the patient inhales is free from high concentrations of CO2, which could be harmful.