317809
Assertion : All carbon atoms in 1,3-butadiene are \(\mathrm{sp}^{2}\) hybridised. Reason : 1,3-Butadiene is a conjugated diene.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
In 1,3-butadiene, \(\left(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}_{2}\right)\) all the carbon atoms are having a pi bond and three sigma bonds. So all carbon atoms are \(\mathrm{sp}^{2}\) hybridised. 1,3 Butadiene has alternate double bonds. So, it is called conjugate diene. Thus, option (2) is correct.
In conjugated system, double bonds are present at alternate positions, in cumulative system, double bonds are present at adjacent positions while in isolated system, there is a large difference, between the positions of double bond.Hence, \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CH}=\mathrm{CH}_{2}\) represents an isolated system.
317809
Assertion : All carbon atoms in 1,3-butadiene are \(\mathrm{sp}^{2}\) hybridised. Reason : 1,3-Butadiene is a conjugated diene.
1 Both Assertion and Reason are correct and Reason is the correct explanation of the Assertion.
2 Both Assertion and Reason are correct but Reason is not the correct explanation of the Assertion.
3 Assertion is correct but Reason is incorrect.
4 Assertion is incorrect but Reason is correct.
Explanation:
In 1,3-butadiene, \(\left(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}_{2}\right)\) all the carbon atoms are having a pi bond and three sigma bonds. So all carbon atoms are \(\mathrm{sp}^{2}\) hybridised. 1,3 Butadiene has alternate double bonds. So, it is called conjugate diene. Thus, option (2) is correct.
In conjugated system, double bonds are present at alternate positions, in cumulative system, double bonds are present at adjacent positions while in isolated system, there is a large difference, between the positions of double bond.Hence, \(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CH}=\mathrm{CH}_{2}\) represents an isolated system.