Vapor pressure reflects what property of a gaseous anesthetic?

• A. Its ability to go across cell membranes
• B. Its ability to be absorbed by the lung tissue
• C. Its tendency to form particles small enough to be sprayed
• D. Its tendency to evaporate

Answer: (D)

Vapor pressure is a measure of how readily a liquid will turn into vapor at a given temperature. It reflects the substance’s tendency to evaporate. In inhaled anesthetics, a higher vapor pressure means the agent readily forms vapor and can be delivered as a gas through a vaporizer, influencing how much of the agent reaches the lungs at a set temperature and flow. The other ideas—cell membrane crossing, absorption by lung tissue, or forming sprayed particles—depend more on solubility, diffusion, or aerosolization tech, not on vapor pressure itself.