Carbon has the unique property to form bonds with other atoms of carbon.
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Carbon forms large number of compounds due to:

Options

A. Catenation only
B. Tetravalency only
C. Both catenation and tetravalency
D. None of the above

Explanation

To answer the question regarding why carbon forms a large number of compounds, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Carbon's Unique Properties**:
- Carbon is a non-metal and has unique properties that allow it to form a wide variety of compounds.

2. **Catenation**:
- One of the key properties of carbon is **catenation**, which is the ability of carbon atoms to bond with each other. This allows carbon to form long chains and complex structures. For example, carbon can bond with itself to create chains of varying lengths, which can be linear or branched.

3. **Tetravalency**:
- Another important property of carbon is **tetravalency**. Carbon has four valence electrons, which means it can form four covalent bonds with other atoms. This allows carbon to bond not only with other carbon atoms but also with a variety of other elements such as hydrogen, oxygen, nitrogen, and halogens (like chlorine and fluorine).

4. **Combination of Properties**:
- The combination of catenation and tetravalency enables carbon to form a vast array of compounds. It can create simple molecules like methane (CH₄) as well as complex macromolecules like proteins and DNA.

5. **Conclusion**:
- Therefore, the large number of carbon compounds can be attributed to its ability to catenate (bond with itself) and its tetravalency (ability to form four bonds). These properties allow for the formation of diverse and complex organic molecules.

### Final Answer:
Carbon forms a large number of compounds due to its unique properties of catenation and tetravalency.

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