Which gives only mono - substituted product ?
o - dinitrobenzene
m - dinitrobenzene
p - dinitrobenzene
Nitrobenzene
B.
m - dinitrobenzene
m - dinitrobenzene gives only mono - substituted product because - NO2 group is meta directing group and only one m - position is possiblein m - dinitrobenzene .
Assertion: Phenol is more reactive than benzene towards electrophilic substitution reaction.
Reason : In the case of phenol, the intermediate carbocation 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.
Benzoic acid is treated with lithium aluminium hydride. The compound obtained is
benzaldehyde
benzyl alcohol
toluene
benzene
Assertion : 2-Butanol on heating with H2SO4 gives 1-butene and 2-butene.
Reason : Dehydration of 2-butanol follows Saytzeff's rule.
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.
Assertion : Ethers behave as bases in the presence of mineral acids.
Reason : It is due to the presence of lone pair of electrons on the oxygen.
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.
Assertion : Benzene diazonium salt on boiling with water forms phenol.
Reason : C- N bond is polar.
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.
Phenol on reaction with Br2 gives :
O - Bromo phenol
p - Bromo phenol
2 , 4 , 6 tribromo phenol
1 , 3 , 5 tribromo benzene