Chapter 21

Sodium benzoate on heating with soda lime gives: (a) Benzenc (b) Methane (c) Calcium benzoate (d) Toluene

The electrophile in the sulphonation of bentene is \(\begin{array}{llll}\text { (c) } \mathrm{HSO}_{4}^{-} & \text {(d) } \mathrm{SO}_{2}\end{array}\) (a) \(\mathrm{SO}_{3}\) (b) \(\mathrm{SO}_{3} \mathrm{H}\)

Which of the following compounds reacts slower than benzene in electrtophilic bromination in the benzene ring? (a) \(\mathrm{C}_{6} \mathrm{H}_{3} \mathrm{NO}_{2}\) (b) \(\mathrm{C}_{6} \mathrm{H}_{2} \mathrm{NH}_{2}\) (c) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{OH}\) (d) \(\mathrm{C}_{6} \mathrm{H}_{3} \mathrm{CH}_{3}\)

The o. \(\mathrm{p}\)-directing but deactivating group is (a) \(-\mathrm{NH}_{2}\) (b) \(\mathrm{OH}\) (c) R (alkyl) (d) \(\mathrm{X}\) (halogen)

When phenol is heated with zinc dust, the major product formed is (a) benzaldehyde (b) phenolphthalein (c) benzene (d) biphenyl

The treatment of benzene with benzoyl chloride in the presence of \(\mathrm{AICl}_{3}\) gives (a) benzaldehyde (b) benzophenone (c) diphenyl (d) cyclohexane

Friedel-Crafts reaction of bromobenzene with methyl chloride gives (a) o-bromotoluene (b) p-bromotoluene (c) und \(p\)-bromotoluene (d) m-bromotoluene

Which one of the following substituents is the strongest ortho- and para- directing group in electrophilic aromatic substitution reactions ? (a) \(-\mathrm{OH}\) (b) \(-\mathrm{Cl}\) (c) \(-\mathrm{OCH}_{3}\) (d) \(-\mathrm{CH}_{3}\)

Benzene reacts with \(\mathrm{Cl}_{2}\) to form BHC in the presence of (a) \(\mathrm{Ni}\) (b) Anh. \(\mathrm{AlCl}_{3}\) (c) Sunlight (d) \(\mathrm{Zn}\)

Carbon-carbon bond length in benzene is ........... than the same bond length in alkenes (a) less (b) more (c) equal (d) none

Which of the following deactivates the ring towards electrophilic substitution? (a) methyl (b) amino (c) hydroxyl un chlor

Toluene by Etard's reaction gives (a) ortho-cresol (b) benzoic acid (c) benzyl alcohol (d) benzaldehyde

The major product obtained on the monobromination (with \(\mathrm{Br}_{2} / \mathrm{FeBr}_{3}\) ) of the following compound ' \(\mathrm{A}\) ' is COc1cccc(C)c1 'A' (a) COc1cccc(C)c1Br (b) COc1ccc(Br)c(C)c1 (c) COc1cc(C)cc(Br)c1 (d) COc1cc(C)ccc1Br

Presence of a nitro group in a benzene ring (a) deactivates the ring towards electrophilic substitution (b) activates the ring towards clectrophilic substitution (c) renders the ring basic (d) deactivates the ring towards nucleophilic substitution

The treatment of bentene with isobutene in the presence of sulphuric acid gives (a) isobutyl benzene (b) tert-butyl benzene (c) \(n\)-Butyl benzene (d) no reaction

Consider the following compounds: (i) ClC(Cl)(Cl)c1ccccc1 (ii) O=C(Cl)c1ccc([N+](=O)[O-])cc1(iii) Cc1ccc(C(=O)Cl)cc1 (iv) O=Cc1ccc(C(=O)Cl)cc1 the correct decreasing order of their reactivity towards hydrolysis is (a) \((\mathrm{iv})>(\mathrm{ii})>(i)>\) (iii) (b) (ii) \(>(i v)>(i)>\) (iii) (c) (ii) > (iv) > (iii) > (i) (d) \((i)>(i i)>(i i i)>(i v)\)

ON=CC(O)c1ccccc1 O=Cc1ccccc1OThe electrophile involved in the above reaction is (a) dichloromethyl cation \(\left({ }^{4} \mathrm{CHCl}_{2}\right)\) (b) dichlorocarbene \(\left(: \overline{C C l}_{2}\right)\) (c) trichloromethyl anion \(\left(\mathrm{CCl}_{2}\right)\) (d) formyl cation \(\left({ }^{+} \mathrm{CHO}\right)\)

Phenyl magnesium bromide reacts with methanol to give (a) a mixture of anisole and \(\mathrm{Mg}(\mathrm{OH}) \mathrm{Br}\) (b) a mixture of benzene and \(\mathrm{Mg}(\mathrm{OMe}) \mathrm{Br}\) (c) a mixture of toluene and \(\mathrm{Mg}(\mathrm{OH}) \mathrm{Br}\) (d) a mixture of phenol and \(\mathrm{Mg}(\mathrm{Me}) \mathrm{Br}\)

CC(C)(C)C \(+\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{Cl} \frac{\text { anhydrous }}{\mathrm{AlCl}_{3}}-\mathrm{A} \stackrel{\text { oxidation }}{\mathrm{CC}}-?\) (a) O=C(O)Cc1ccccc1 (b) O=Cc1ccccc1 (c) O=C(O)c1ccccc1 (d) none of these

The reaction of benzene that involves a neutral electrophile is (a) bromination (b) nitration (c) sulphonation (d) gatterman koch reaction

Cumene can be prepared from benzene via its Friedel Craft reaction with the following (a) \(n\)-propyl chloride (b) isopropyl chloride (c) both of these (d) none of these