PASSAGE-I : Diamond and graphite are two allotropic forms of carbon which are crystalline in nature. They differ physically but chemically they are similar. Diamond is the hardest crystalline form of carbon. In diamond each carbon atom is linked to four other carbon atoms by covalent bonds. In graphite, each carbon atom is linked to three other carbon atoms by covalent bond. Graphite is relatively soft and greasy. It is a good conductor or electricity.
Which of the following is a goos conductor of heat and electricity?

Options

A. Coal
B. Diamond
C. Charcoal
D. Graphite

Answer

To solve the question regarding which form of carbon is a good conductor of heat and electricity, we can follow these steps:

### Step 1: Understand the Properties of Allotropic Forms of Carbon
- **Diamond**: Each carbon atom is bonded to four other carbon atoms through strong covalent bonds, making it extremely hard. However, it does not conduct electricity or heat well due to the lack of free electrons.
- **Graphite**: Each carbon atom is bonded to three other carbon atoms, forming layers that can slide over each other. The presence of free electrons in graphite allows it to conduct electricity and heat.

### Step 2: Identify the Conductivity of Each Form
- **Diamond**: Poor conductor of heat and electricity.
- **Graphite**: Good conductor of heat and electricity due to the presence of delocalized electrons.

### Step 3: Conclusion
Based on the properties of diamond and graphite, the answer to the question "Which of the following is a good conductor of heat and electricity?" is **Graphite**.

### Final Answer
**Graphite is a good conductor of heat and electricity.**

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