A primary amine has amino group `(-NH_(2))` attached to :-

Options

A. A primary carbon atom only
B. A secondary carbon atom only
C. A tertiary carbon atom only
D. A primary, secondary or tertiary carbon atom

Answer

To determine the attachment of the amino group (-NH2) in a primary amine, we need to understand the definitions of primary, secondary, and tertiary carbon atoms.

### Step-by-Step Solution:

1. **Understanding Carbon Types**:
- **Primary Carbon**: A carbon atom that is attached to only one other carbon atom. For example, in a molecule like ethyl amine (C2H5NH2), the carbon to which the amino group is attached is a primary carbon because it is connected to only one other carbon.
- **Secondary Carbon**: A carbon atom that is attached to two other carbon atoms. For example, if the amino group is attached to a carbon that is connected to two other carbons, it is a secondary carbon.
- **Tertiary Carbon**: A carbon atom that is attached to three other carbon atoms. If the amino group is attached to a carbon that is connected to three other carbons, it is a tertiary carbon.

2. **Identifying the Primary Amine**:
- A primary amine is defined as an amine where the amino group (-NH2) is attached to a carbon atom. The key characteristic of a primary amine is that the carbon atom to which the amino group is attached can be a primary, secondary, or tertiary carbon.

3. **Conclusion**:
- Therefore, the amino group in a primary amine can be attached to a primary carbon, a secondary carbon, or a tertiary carbon. This means that the correct answer to the question is that a primary amine can have the amino group attached to a primary, secondary, or tertiary carbon atom.

### Final Answer:
A primary amine has an amino group (-NH2) attached to a primary, secondary, or tertiary carbon atom.

---