Kaplan Nursing Entrance Exam Practice 2026 – Comprehensive Prep

In the context of gas properties, "pressure" specifically refers to the force exerted by gas particles when they collide with the walls of their container. This concept stems from the kinetic molecular theory, which explains that gas particles are in constant motion and collide with one another and with the surfaces around them. These collisions produce a force that, when distributed over a specific area, is quantified as pressure.

Understanding pressure is crucial because it plays a fundamental role in various physiological processes, such as respiration, where the pressure changes in the lungs facilitate the movement of air during inhalation and exhalation. The other terms presented relate to different properties of gases: "mass per unit volume," for example, refers to density rather than pressure, while "temperature" and "speed of the gas molecules" are connected to the kinetic energy and motion of the gas particles, respectively, rather than the pressure they exert.