591.

Among the following the aromatic compound is

• 

• 

• 

• 

Assertion : Styrene on reaction with HBr gives 2-bromo-2-phenyl ethane.

Reason: Benzyl radical is more stable than alkyl radical.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If resason is true but assertion is false

• If both assertion and reason are false.

Assertion : The pK_a of acetic acid is lower than that of phenol.

Reason : Phenoxide ion is more resonance stabilised

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false.

Which of the following is aromatic?

Which ofthe following is most stable carbocation?

• CH₃⁺

• CH₃CH₂$\stackrel{+}{\mathrm{C}}$H₂

• CH₃$$\begin{gathered} \stackrel{ \\ +}{\mathrm{C}} \end{gathered}$$HCH₃

• CH₃-(CH₃)$\stackrel{+}{\mathrm{C}}$-CH₃

Assertion : Alkyl benzene is not prepared by Friedel-Crafts alkylation of benzene.

Reason : Alkyl halides are less reactive than acyl halides.

• If both assertion and reason are true and the reason is the correct explanation of the assertion.

• If both assertion and reason are true and the reason is not the correct explanation of the assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

Rate determining step in nitration of benzene is

• formation of NO₂⁺

• formation of carbocation

• replacement of H atom

• none of these.

1,4-dimethylbenzene on heating with anhydrous AlCl₃ and HCl produces

• 1, 2-dimethylbenzene

• 1, 3-dimethylbenzene

• 1, 2, 3-trimethylbenzene

• ethylbenzene

In 2-butene, which one of the following statements is true?

• C₁-C₂ bond is sp³-sp³ -$\mathrm{\sigma }$-bond

• C₂-C₃ bond is sp³-sp² -$\mathrm{\sigma }$-bond

• C₁-C₂ bond is an sp³-sp² -$\mathrm{\sigma }$-bond

• C₁-C₂ bond is an sp²-sp² -$\mathrm{\sigma }$-bond

The stability of Me₂C=CH₂ is more than that of MeCH₂CH=CH₂ due to:

• inductive effect of the Me groups

• resonance effect of the Me groups

• hyperconjugation effect of the Me groups

• resonance as well as the inductive effect of the Me groups