The compound prepared by a substitution reaction of benzene is
acetophenone
glyoxal
cyclohexane
hexabromo cyclohexane
The number of sigma (σ) and pi () bonds present in benzene respectively are :
12, 6
6, 6
6, 12
12, 3
Which of the following compound(s) has 'Z' configuration ?
(i) only
(ii) only
(iii) only
(i) and (iii) only
The structure of the compound formed, when nitrobenzene is reduced by lithium aluminium hydride (LiAlH4) is
In which of the following, ortho/para substitution by an electrophile is very facile?
Ntrobenzene
Phenol
Benzoic acid
Acetophenone
B.
Phenol
-OH group is ortho/para directing and makes the benzene ring more active towards electrophilic substitution. Thus, ortho/para substituton m phenol by an electrophile is very facile.
Reduction of nitrobenzene with Zn and alcoholic KOH solution results in the formation of the following compound.
hydrazobenzene
azobenzene
aniline
phenylhydroxylamine
Nitrobenzene on reduction using zinc in alkaline medium results in X. The number of sigma (σ) and pi () bonds in X is-
24 σ, 7
24 σ, 6
27 σ, 7
24 σ, 6