The movement of colloidal particles under an applied electric potential is termed as

Options

A. electrophoresis
B. Osmosis
C. catalyst
D. ultrafiltration

Answer

To solve the question "The movement of colloidal particles under an applied electric potential is termed as," we will analyze the terms related to colloidal chemistry and identify the correct term.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the movement of colloidal particles when an electric potential is applied. This movement is influenced by the electric field created by the potential.

2. **Identifying Key Terms**:
- **Electrophoresis**: This term refers specifically to the movement of charged particles in a liquid under the influence of an electric field. Colloidal particles can carry a charge and will migrate towards the electrode of opposite charge when an electric field is applied.
- **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. It does not involve electric potential.
- **Catalyst**: A substance that increases the rate of a chemical reaction by lowering the activation energy. It is unrelated to the movement of colloidal particles.
- **Ultrafiltration**: A process used to separate colloidal particles from soluble impurities using special filters. This process does not involve electric potential.

3. **Conclusion**: Based on the definitions, the correct term that describes the movement of colloidal particles under an applied electric potential is **Electrophoresis**.

### Final Answer:
The movement of colloidal particles under an applied electric potential is termed as **Electrophoresis**.

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