__________are used in electrostatic precipitators.

Options

A. Catalysts
B. Absorbers
C. Electrodes
D. Chemicals

Answer

To answer the question "__________ are used in electrostatic precipitators," we need to understand what electrostatic precipitators (ESPs) are and how they function.

### Step-by-Step Solution:

1. **Identify the Function of Electrostatic Precipitators (ESPs)**:
- ESPs are devices designed to remove particulate matter (like dust and smoke) from industrial emissions and exhaust gases. They are commonly used in factories and vehicles to clean the air.

2. **Understand the Working Principle**:
- ESPs operate by using electrical energy to charge the particles in the gas stream. This charging process allows the particles to be attracted to oppositely charged plates.

3. **Determine the Components Used in ESPs**:
- The key components in an electrostatic precipitator are charged plates that create an electric field. These plates are responsible for attracting and collecting the charged particles.

4. **Identify the Correct Term**:
- The charged plates in ESPs are referred to as "electrodes." They can be either positively or negatively charged, and they play a crucial role in the operation of the ESP by facilitating the removal of particulate matter.

5. **Eliminate Other Options**:
- The other options provided (catalyst, absorber, chemicals) do not apply to the function of ESPs:
- Catalysts are used in catalytic converters, not in ESPs.
- Absorbers are not relevant in the context of ESPs, as they do not perform the same function.
- Chemicals are not used in the process of electrostatic precipitation.

### Final Answer:
Electrodes are used in electrostatic precipitators.

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