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This section contains assertion and reas...

This section contains assertion and reason type questions. Each question has 4 choice (1), (2),(3), and (4), out of which only one is correct.
Assertion (A) Vinylacetylene is but-1-ene – 3 – yne.
Reason ( R) Double bond is preferred over triple bond while naming the organic compound.

A

Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion

B

Both Assertion and Reason are correct but reason is not the correct explanation of Assertion

C

Assertion is correct but Reason is incorrect

D

Both Assertion and Reason are incorrect

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reason type question regarding vinylacetylene, we will analyze both the assertion and the reason step by step. ### Step 1: Analyze the Assertion **Assertion (A): Vinylacetylene is but-1-ene-3-yne.** 1. **Identify Vinylacetylene**: Vinylacetylene is a compound that contains both a vinyl group (which is a carbon-carbon double bond) and an acetylene group (which is a carbon-carbon triple bond). 2. **Determine the Structure**: The structure of vinylacetylene can be represented as follows: - The longest carbon chain consists of four carbon atoms. - The first carbon has a double bond (alkene), and the third carbon has a triple bond (alkyne). 3. **IUPAC Naming**: According to IUPAC nomenclature: - The double bond is indicated by “-ene” and the triple bond by “-yne”. - Since there is both a double bond and a triple bond, we must prioritize the double bond when numbering the carbon chain. - Thus, the correct name for vinylacetylene is indeed but-1-ene-3-yne. **Conclusion for Assertion**: The assertion is correct. ### Step 2: Analyze the Reason **Reason (R): Double bond is preferred over triple bond while naming the organic compound.** 1. **Understanding Priority in Naming**: In organic nomenclature, when both double and triple bonds are present, the double bond is given higher priority. 2. **Lower Numbering Rule**: The lowest possible number is assigned to the double bond when numbering the carbon chain. This is known as the lower number rule. 3. **Explanation of Preference**: The reason states that the double bond is preferred over the triple bond, which aligns with the IUPAC naming conventions. **Conclusion for Reason**: The reason is also correct and provides a valid explanation for the assertion. ### Final Conclusion Both the assertion and the reason are correct, and the reason correctly explains the assertion. ### Answer Choice The correct answer is: **(1)** Both A and R are correct, and R is the correct explanation for A. ---
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