A gas moves from an area of ________ partial pressure to an area of ________ partial pressure.

• A. lower; higher
• B. equal; equal
• C. higher; lower
• D. zero; maximum

Answer: (C)

Verified step by step guidance

1. Understand the concept of gas movement in terms of partial pressure: gases naturally move from regions of higher partial pressure to regions of lower partial pressure.
2. Recall that partial pressure is the pressure exerted by a single type of gas in a mixture, and it drives the diffusion process.
3. Identify that gas molecules tend to diffuse down their partial pressure gradient, meaning from an area where their partial pressure is higher to where it is lower.
4. Apply this principle to the problem: the gas moves from an area of higher partial pressure to an area of lower partial pressure.
5. Conclude that the correct answer is 'higher; lower' because this matches the natural direction of gas movement driven by partial pressure differences.