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9. Aromatic Hydrocarbons eLearn.Punjab

EXERCISE

Q1. Fill in the blanks.
i) The term aromatic was derived from Greek word___________ meaning
_______________.
ii) Aromatic hydrocarbons include benzene and all those compounds which
are ___________ related to benzene.
iii) ______________is recognized as the simplest member of the class of
Aromatic Hydrocarbons.
iv) Benzene has_______________structure.
v) These removal of hydrogen atom from aromatic hydrocarbons gives a
radical. The radicals are called__________ .
vi) Benzene was discovered by Michael Faraday in_______ .
vii) The unhybridized 2pz orbitals in benzene partially overlap to form a
___________ of electron cloud.
viii) The introduction of halogen group in benzene ring is called_______.
ix) The molecular formula of C6H6 indicates that it is highly__________
compound.
x) On oxidation in the presence of V2O5 benzene gives__________.

Q.2 Indicate True or False.

i) Benzene is more reactive than alkene and less reactive than alkane.

ii) Benzene has a pentagonal structure. o

iii) The C-C bond length in benzene molecule is 1.397 A.

iv) The state of hybridization of carbon in benzene molecule is sp3.

v) There are six sigma bonds in benzene molecule.

vi) Halogenonium ion produced in electrophilic substitution reactions is a

powerful electrophile.

vii) In electrophilic substitution reactions, addition products are favourable.

viii) Sulphonation is carried out when benzene is heated with conc. HNO3.
ix) In ozonolysis benzene directly gives glyoxal.

x) Benzene has five resonace contributing structures.

Q.3. Multiple choice questions. Encircle the correct answer.

i) The benzene molecule contains (b) Two double bonds
(a) Three double bonds (d) Delocalized π -electron charge
(c) One double bond

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