Smallest possible unit of a compound which has independent existence is

Options

A. molecule
B. atom
C. ion
D. electron

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the smallest unit of a compound that can exist independently.

2. **Defining a Compound**: A compound is defined as a substance formed when two or more different elements are chemically bonded together.

3. **Identifying the Smallest Unit**: The smallest unit of a compound that retains its chemical properties and can exist independently is known as a molecule.

4. **Differentiating Between Molecules and Atoms**: It is important to note that while atoms are the smallest units of elements, molecules are the smallest units of compounds. For example, in the case of water (H₂O), the molecule consists of two hydrogen atoms and one oxygen atom bonded together.

5. **Conclusion**: Therefore, the smallest possible unit of a compound which has independent existence is a molecule.

**Final Answer**: Molecule

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