The tendency of carbon atoms to form long chains is called -

Options

A. Polymerisation
B. Catenation
C. Substitution
D. Bonding

Explanation

To solve the question regarding the tendency of carbon atoms to form long chains, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the specific term that describes the ability of carbon atoms to link together to form long chains.

2. **Reviewing the Options**: The options provided are:
- A) Polymerization
- B) Catenation
- C) Substitution
- D) Bonding

3. **Analyzing Each Option**:
- **Polymerization**: This is a process where small units called monomers combine to form a larger molecule known as a polymer. This does not specifically refer to the ability of carbon to form long chains.
- **Catenation**: This is the property of certain elements, particularly carbon, to form long chains and cyclic structures by bonding with themselves. This is the correct term for the tendency of carbon atoms to link together.
- **Substitution**: This refers to a reaction where an atom or group of atoms in a compound is replaced by another atom or group. This does not describe the formation of long chains.
- **Bonding**: While bonding is essential for forming any molecule, it does not specifically refer to the tendency of carbon to create long chains.

4. **Identifying the Correct Answer**: Based on the analysis, the correct answer is **Catenation** (Option B).

### Final Answer:
The tendency of carbon atoms to form long chains is called **Catenation**.

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