(c) I > II > III (d) I = II > III

4. Which one of the following is a free radical substitution reaction?

5. The ortho/para directing group among the following is

(a) –COOH        (b) –CN

(c)        (d)

6. The treatment of benzene with isobutene in the presence of sulphuric acid gives

(a) isobutyl benzene        (b) tert-butyl benzene

(b) n-Butyl benzene        (d) No reaction

7. Benzoic acid, when heated with soda lime yields

(a) benzaldehyde         (b) benzene

(c) toluene                  (d) benzylalcohol

(e) cyclohenxane

10. In Friedel Craft’s alkylation, besides AlCl3, the other reactants are

12. Benzene does not undergo addition reactions easily because

(a) It has a cyclic structure

(b) Double bonds in it are very strong

(c) Resonance stabilized system is to be preserved

(d) It has six hydrogen atoms

13. The melting points of isomeric xylenes are in the order:

(a) p-xylene > o-xylene > m-xylene (b) p-xylene > m-xylene >o-xylene

(c) o-xylene > m-xylene > p-xylene (d) p-xylene > p-xylene > m-xylene

14. The correct order of C – C bond lengths in benzene (I), ethane (II), ethylene (III) and

acetylene (IV) is

(a) II >III > IV > I         (b) IV > III > II > I

(c) II > I > III > IV        (d) IV > III > I > II

17. The correct order of reactivity towards the electrophilic substitution of the compounds,

aniline (I), benzene (II) and nitrobenzene (III), is

(a) II > III > I         (b) I > II > III

(c) I > II > III         (d) III > II > I

19. A group which deactivates the benzene ring towards electrophilic substitution but directs

the incoming group towards o- and p- positions is

(a) –NH2           (b) –Cl

(c) –NO2          (d) –C2H6

20. Which species represents the electrophile in aromatic nitration?

21. The most reactive compound for electrophilic nitration is

(a) Benzene             (b) Nitrobenzene

(c) Benzoic acid        (d) Toluene

22. The function of AlCl3 in Friedel Crafts reaction is

(a) to absorb water                    (b) to absorb HCl

(c) to produce electrophile         (d) to produce nucleophile

24. Benzene reacts with CH3COCl gives

(a) Chlorobenzene            (b) Toluene

(c) Benzyl chloride           (d) Acetophenone

1. Which of the following are true?

(a) Benzene tends to undergo substitution rather than addition reactions

(b) All hydrogen atoms of benzene are equivalent

(c) The carbon-carbon bonds of benzene are alternatively short and long around the ring.

(d) There can be two o-disubstituted derivatives

4. Which of the following characteristics does an aromatic compound exhibit?

(a) It should have (4n + 2) π-electrons         (b) It should be planar and conjugated

(c) It should have 4n π-electrons                 (d) It should process high resonance energy

7. Which of the following statements are true for benzene?

(a) It is a flat, regular, hexagonal molecule

(b) Each C – C – C angle is 109°28′

(c) The C – C bond length is 1.39Å

(d) All carbon atoms are sp³ hybridised

9. Toluene reacts with ethyl bromide in the presence of anhydrous AlCl3 to produce

(a) o-ethyltoluene           (b) p-ethyltoluene

(c) m-ethyltoluene          (d) a mixture of all of these

11. The sulphonation of toluene with oleum at 35°C produces

(a) p-toluene sulphonic acid

(b) o-toluene sulphonic acid

(c) m-toluene sulphonic acid

(d) a mixture of (a), (b) and (c) in approximately equal proportions

14. Which of the following statements are correct?

(a) An activating group is an electron-releasing group

(b) An activating group activates all positions of the benzene ring.

(c) The effect of any group –– whether activating or deactivating –– is the strongest at the ortho- and para-positions in the benzene ring.

(d) An activating group activates only the ortho- and para-positions in the benzene ring.

15. The necessary conditions for halogenation are

(a) low temperature                             (b) darkness

(c) the presence of a halogen carrier     (d) none of these

16. Benzene can undergo

(a) substitution          (b) addition

(c) elimination           (d) oxidation

17. Which of the following statements about the nitration of aromatic compounds are correct?

(a) The rate of nitration of toluene is greater than that of benzene

(b) The rate of nitration of benzene is almost the same as that of hexadeutrobenzene

(c) The rate of nitration of benzene is greater than that of heaxadeutrobenzene

(d) Nitration is an electrophilic substitution reaction

19. Which of the following can be represented by a resonance hybrid?

(a) Sulphur trioxide           (b) Benzene

(c) Toluene                       (d) Benzene sulphonic acid

21. Toluene, when treated with Br2/Fe, gives p-bromotoluene as the major product because

the –CH3 group

(a) is ortho - para directing                                (b) is meta directing

(c) activates of the ring by hyperconjugation       (d) deactivates the ring

22. What is the end product obtained by nitration of toluene?

(a) o-Nitrotoluene             (b) p-Nitrotoluene

(c) 2,4-Dinitrotoluene       (d) 2,4,6-Trinitrotoluene

23. Ozonolysis of p-xylene gives

(a) Glyoxal                  (b) Methyl glyoxal

(c) Both of these         (d) None of these

25. During electrophile substitution in benzene, the intermediate species involved is

(a) Carbocation    (b) Carbanion

(c) Free radical     (d) None of these