What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?

Explanation

To answer the question regarding the two properties of carbon that lead to the vast number of carbon compounds, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Tetravalency**:
- Carbon has a valency of 4, which means it can form four bonds with other atoms. This property is known as tetravalency.
- Each carbon atom has four electrons in its outermost shell and needs four more electrons to complete its octet, which is a stable configuration.
- For example, in methane (CH₄), one carbon atom forms four single bonds with four hydrogen atoms, fulfilling its tetravalent nature.
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