Assertion: Alkenes are easily attacked by electrophilic reagents.
Reason: Alkenes are unstable molecules in comparison to alkenes.

Options

A. If both assertion and reson are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To solve the assertion and reason question, let's break it down step by step.

### Step 1: Analyze the Assertion
**Assertion:** Alkenes are easily attacked by electrophilic reagents.

- Alkenes contain a carbon-carbon double bond (C=C), which is a region of high electron density. This makes alkenes nucleophilic in nature, meaning they can donate electrons.
- Electrophilic reagents are species that seek electrons and can react with nucleophiles.
- For example, when ethene (C2H4) reacts with bromine (Br2), the double bond attacks the bromine, leading to the formation of 1,2-dibromoethane. This confirms that alkenes are indeed easily attacked by electrophilic reagents.

**Conclusion for Assertion:** The assertion is true.

### Step 2: Analyze the Reason
**Reason:** Alkenes are unstable molecules in comparison to alkanes.

- While it is true that alkenes are generally more reactive than alkanes, the statement that they are "unstable" is misleading. Alkenes are more reactive due to the presence of the double bond, which is a weaker pi bond compared to the sigma bonds in alkanes.
- Alkanes (like ethane) are saturated hydrocarbons and do not have double bonds, making them less reactive than alkenes. However, this does not mean that alkenes are "unstable" in a general sense; they are simply more reactive due to their structure.

**Conclusion for Reason:** The reason is true, but it does not correctly explain the assertion.

### Step 3: Determine the Relationship
- Both the assertion and the reason are true statements.
- However, the reason provided does not adequately explain why alkenes are more reactive than alkanes.

### Final Conclusion
Based on the analysis:
- Both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Answer Option
The correct answer is: **Option B** - Both assertion and reason are true, but reason is not the correct explanation of assertion.

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