Carbon rods, used as electrodes are made up of:

Options

A. graphite
B. wood
C. iron
D. diamond

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks what material carbon rods, used as electrodes, are made of.

2. **Identifying the Options:**
The options provided are graphite, wood, iron, and diamond.

3. **Analyzing Each Option:**
- **Graphite:** Graphite is a form of carbon that is known for its excellent electrical conductivity. It has a structure that allows electrons to move freely, making it suitable for use as an electrode.
- **Wood:** Wood is an organic material that is not a conductor of electricity and therefore not suitable for use as an electrode.
- **Iron:** While iron is a conductor, it is not typically used for electrodes in electrolysis due to its tendency to corrode.
- **Diamond:** Diamond is another form of carbon but is an insulator and does not conduct electricity.

4. **Conclusion:**
Based on the analysis, the correct answer is that carbon rods used as electrodes are made of **graphite**.

**Final Answer:**
Carbon rods, used as electrodes, are made up of **graphite**.

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