What do you understand by covalency? Find the covalency of the underlined element in the following compounds :
` underline(N)H_3`

Explanation

### Step-by-Step Solution:

1. **Understanding Covalency**:
- Covalency refers to the ability of an atom to share its electrons with other atoms in order to achieve a full outer shell of electrons, typically an octet (8 electrons) for main group elements.

2. **Identifying the Element**:
- In the compound NH₃ (ammonia), the underlined element is nitrogen (N).

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