Question

Diffusion governed by concentration gradient follows

• A. Newton's law
• B. Fick's law
• C. Hooke's law
• D. Faraday's law

Hint:

Fick's First Law is analogous to Fourier's Law of heat conduction and Ohm's Law of electrical conduction, where flux is proportional to a driving force gradient.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
The question asks for the fundamental law that governs mass transport (diffusion) under the influence of a concentration gradient.

Step 2: Key Formula or Approach:
For steady-state diffusion, Fick's First Law relates the diffusion flux (\( J \)) to the concentration gradient:
\[ J = -D \frac{dC}{dx} \]
where:
\( J \) is the diffusion flux,
\( D \) is the diffusion coefficient, and
\( \frac{dC}{dx} \) is the concentration gradient.
For non-steady-state diffusion, Fick's Second Law is used:
\[ \frac{\partial C}{\partial t} = D \frac{\partial^2 C}{\partial x^2} \]

Step 3: Detailed Explanation:

• Fick's Laws of Diffusion: These laws mathematically describe the process of diffusion, illustrating how atoms or molecules move from regions of high concentration to regions of low concentration.

• Comparison with Other Options:
-

Newton's law (Option A) refers to viscosity in fluids or laws of classical mechanics.
-

Hooke's law (Option C) governs the linear elastic behavior of solids, stating that stress is proportional to strain.
-

Faraday's law (Option D) describes electromagnetic induction or electrochemical electrolysis.


Step 4: Final Answer:
Therefore, concentration-gradient-driven diffusion is described by Fick's law, which matches Option (B).