At what temperature is oxygen's critical temperature defined?

• A. -100C
• B. -118C
• C. -120C
• D. -130C

Answer: (B)

Oxygen's critical temperature is an important physical property, defined as the highest temperature at which a gas can exist as a liquid, regardless of the pressure applied. For oxygen, this critical temperature is approximately -118°C.

At this temperature, oxygen can be liquefied if the pressure is sufficiently increased. Understanding the critical temperature is crucial in various applications, especially in anesthesiology and gas storage, because it determines the conditions under which oxygen can be effectively stored and used in liquid form.

Oxygen's characteristics at temperatures above its critical temperature play a significant role in its behavior in anesthesia machines and other medical applications. By knowing that -118°C signifies the critical point, healthcare professionals can ensure the appropriate handling and storage of oxygen to maintain its efficacy and safety in medical settings.