What is the primary factor that drives the process of diffusion?

• A. Pressure gradient
• B. Temperature gradient
• C. Volume gradient
• D. Concentration gradient

Answer: (D)

Verified step by step guidance

1. Understand the concept of diffusion: Diffusion is the movement of particles from an area of higher concentration to an area of lower concentration. This process continues until equilibrium is reached, meaning the concentration is uniform throughout the space.
2. Identify the primary factor: The primary factor that drives diffusion is the concentration gradient. A concentration gradient exists when there is a difference in the concentration of particles in two regions.
3. Explain the role of concentration gradient: The concentration gradient provides the 'driving force' for diffusion. Particles naturally move down the concentration gradient, from areas of high concentration to areas of low concentration, due to random motion.
4. Consider other factors: While pressure, temperature, and volume can affect the rate of diffusion, they are not the primary driving force. For example, higher temperatures can increase the kinetic energy of particles, speeding up diffusion, but the concentration gradient is still the main factor.
5. Summarize the concept: In summary, diffusion is primarily driven by the concentration gradient, which causes particles to move from regions of high concentration to regions of low concentration until equilibrium is achieved.