Assertion:- Acrylic acid is unsaturated compound.
Reason:- One double bond between the carbon atoms is present

Options

A. If both Assertion `&` Reason are True `&` the Reason is a correct explanation of the Assertion.
B. If both Assertion `&` Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion `&` Reason are False.

Answer

### Step-by-Step Text Solution:

1. **Understanding Unsaturated Compounds**:
- Unsaturated compounds are defined as those that contain at least one pair of adjacent carbon atoms linked by a multiple bond (either a double bond or a triple bond).

2. **Identifying the Structure of Acrylic Acid**:
- Acrylic acid is a carboxylic acid, which means it contains the functional group -COOH. Its chemical formula is C3H4O2.
- The structure of acrylic acid can be represented as:
\[ \text{H}_2C=CH-COOH \]
- In this structure, there is a double bond between the first two carbon atoms (C=C).

3. **Analyzing the Assertion**:
- The assertion states that "Acrylic acid is an unsaturated compound."
- Since acrylic acid contains a double bond between adjacent carbon atoms, this assertion is true.

4. **Analyzing the Reason**:
- The reason states that "One double bond between the carbon atoms is present."
- This is also true, as the structure of acrylic acid shows that there is indeed one double bond between the first two carbon atoms.

5. **Conclusion**:
- Both the assertion and the reason are true. Furthermore, the reason provides a correct explanation for the assertion, as the presence of the double bond is what classifies acrylic acid as an unsaturated compound.

### Final Answer:
Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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