Multiple Choice QuestionsPhenol and benzoic acid may be distinguished by :
NaHCO3
NaOH
Na
PCl5
A.
NaHCO3
Phenol and benzoic acid can be distinguished by NaHCO3 .Being stronger acid , only benzoic acid reacts with it .
Most acidic is :
D.
Phenol is acidic in nature and the acidic nature of phenol is increased by the presence of - I (electron attracting) groups at o - and / or p - position of the - OH group .However benzoic acid is more acidic than nitro - phenol .
The major organic product in the reaction,
CH3 -O- CH(CH3)2 + HI → Product is:
CH3OH + (CH3)2 + CHI
ICH2OCH(CH3)2
CH3O CI(CH3)2
CH3O CI(CH3)2
D.
CH3O CI(CH3)2
Z X Y Z
Here Z is :
CH3-CH2-CH2-OH
(CH3)2-C-OH
CH3-CH(OH)-CH3
none of above
C.
CH3-CH(OH)-CH3
CH3-CH(OH)-CH3 CH3-CH(Cl)CH3 CH3-CH=CH2 Z
Phenol on reaction with Br2 gives :
O - Bromo phenol
p - Bromo phenol
2 , 4 , 6 tribromo phenol
1 , 3 , 5 tribromo benzene
C.
2 , 4 , 6 tribromo phenol
Phenol reacts with Br2 as follows ;
+ Br2 
Assertion : t-Butyl methyl ether is not prepared by the reaction of t-butyl bromide with sodium methoxide.
Reason : Sodium methoxide is a strong nucleophile.
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.
B.
If both assertion and reason are true but reason is not the correct explanation of assertion.
In Williamson's synthesis, if a tertiary alkyl halide is used, an alkene is the only reaction product and no ether is formed.
(CH3)3CBr + NaOCH3 → (CH3)2C=CH2 + NaBr
It is because alkoxides are not only nucleophiles but also strong bases as well. They react with alkyl halides leading to elimination reaction.
Compound reacting with alkaline KMnO4 :
(CH3)3-C-OH
(CH3)2-CH-OH
(CH3)3-C-CH2OH
none of the above
B.
(CH3)2-CH-OH
Only 1° alochol and 2° alcohol react with alkaline KMnO4 .
In Williamson's synthesis, ethoxyethane is prepared by :
passing ethanol over heated alumina
heating sodium ethoxide with ethyl bromide
treating ethyl alcohol with excess of H2SO4 at 430-440 K
heating ethanol with dry Ag2O
B.
heating sodium ethoxide with ethyl bromide
In Williamson's synthesis, ethoxyethane is prepared by heating sodium ethoxide with ethyl bromide. It can be represented by the following equation:
Lucas reagent reacts fastest with :
butanol - 1
butanol - 2
2 - methyl - propanol - 2
2 - methyl - propanol - 1
C.
2 - methyl - propanol - 2
Lucas reagent (ZnCl2/HCl) reacts fastest with 3° alcohols such as 2 - methyl propanol - 2 [(CH3)3-C-OH] .
Phenol reacts with chloroform in presence of
H2SO4
KOH
NaNO2/ HCl
G.R.
B.
KOH
Phenol reacts with chloroform in presence of potassium hydroxide to form salicylaldehyde.
