Which of the following factors results in an increase in the rate of diffusion?

• A. Increasing the temperature
• B. Increasing the molecular weight of the diffusing substance
• C. Decreasing the surface area available for diffusion
• D. Decreasing the concentration gradient

Answer: (A)

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. The rate of diffusion can be influenced by several factors.
2. Consider the effect of temperature: Increasing the temperature generally increases the kinetic energy of molecules, causing them to move faster. This increased movement can lead to a higher rate of diffusion.
3. Analyze the impact of molecular weight: Heavier molecules (higher molecular weight) tend to move more slowly than lighter ones. Therefore, increasing the molecular weight of the diffusing substance would typically decrease the rate of diffusion.
4. Evaluate the role of surface area: A larger surface area allows more particles to diffuse at once, potentially increasing the rate of diffusion. Conversely, decreasing the surface area would likely reduce the rate of diffusion.
5. Examine the concentration gradient: A higher concentration gradient (a larger difference in concentration between two areas) usually results in a faster rate of diffusion. Decreasing the concentration gradient would therefore decrease the rate of diffusion.