The movement of free atoms from higher concentration to lower concentration is called

Options

A. Osmosis
B. Diffusion
C. Endosmosis
D. Exosmosis

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the movement of free atoms from an area of higher concentration to an area of lower concentration. This is a fundamental concept in biology related to the movement of particles.

2. **Identifying the Options**: The options provided are:
- A) Osmosis
- B) Diffusion
- C) Endosmosis
- D) Exosmosis

3. **Defining the Terms**:
- **Osmosis**: This is the movement of solvent molecules through a semi-permeable membrane from a region of lower solute concentration to a region of higher solute concentration.
- **Diffusion**: This is the process where particles (such as atoms or ions) move from an area of higher concentration to an area of lower concentration until equilibrium is reached.
- **Endosmosis**: This refers to the movement of solvent into a cell through a semi-permeable membrane.
- **Exosmosis**: This is the movement of solvent out of a cell through a semi-permeable membrane.

4. **Analyzing the Options**:
- Since the question specifically mentions "free atoms" moving from higher to lower concentration, we can eliminate osmosis, endosmosis, and exosmosis, as they involve the movement of solvent or solute through membranes and do not apply to free atoms.

5. **Conclusion**: The correct answer is **Diffusion**, as it directly describes the movement of free atoms from a region of higher concentration to a region of lower concentration.

### Final Answer:
The movement of free atoms from higher concentration to lower concentration is called **Diffusion**.

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