What should be present in a substance to make it a conductor of electricity ?

Options

A. Strongly held electrons
B. Strongly held protons
C. Free electrons
D. Free protons

Answer

To determine what should be present in a substance to make it a conductor of electricity, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Conductors**:
- Conductors are materials that allow electricity to flow through them easily. This is due to the presence of certain particles within the material.

2. **Identifying Key Particles**:
- In solids, the main particles involved in conducting electricity are electrons. Specifically, we need to consider how these electrons are held within the material.

3. **Free Electrons vs. Strongly Held Electrons**:
- If electrons are strongly held by the atoms in a substance, they cannot move freely. This means that electricity cannot pass through the material efficiently.
- Conversely, if electrons are free (not tightly bound to any particular atom), they can move throughout the material, allowing electricity to flow.

4. **Conclusion**:
- Therefore, for a substance to be a good conductor of electricity, it must have **free electrons**. These free electrons are responsible for carrying the electric charge through the material.

### Final Answer:
Free electrons should be present in a substance to make it a conductor of electricity.

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