Molecule is the smallest particle of a substance which is capable of..........

Answer

To answer the question "Molecule is the smallest particle of a substance which is capable of...", we can break down the solution into several steps:

### Step-by-Step Solution:

1. **Definition of a Molecule**: A molecule is defined as the smallest particle of a substance that retains all the properties of that substance. It is formed when two or more atoms bond together chemically.

2. **Independent Existence**: Molecules can exist independently. This means that a molecule can exist on its own without needing to be part of a larger structure or compound.

3. **Examples of Molecules**:
- **Molecules of Compounds**: For example, water (H₂O) is a molecule made up of two hydrogen atoms and one oxygen atom. It retains the properties of water.
- **Molecules of Elements**: Some elements exist as single atoms, such as noble gases (e.g., helium, neon). These noble gas atoms are also considered molecules because they can exist independently.

4. **Atoms vs. Molecules**: While atoms are the basic units of matter, they do not always exist independently. For example, most atoms combine to form molecules. However, in the case of noble gases, single atoms can exist independently as molecules.

5. **Conclusion**: Therefore, the complete statement is: "A molecule is the smallest particle of a substance which is capable of independent existence and retains all the properties of that substance."

### Final Answer:
A molecule is the smallest particle of a substance which is capable of independent existence and retains all the properties of that substance.

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