Multiple Choice QuestionsWhich of the following compounds can be used as antifreeze in automobile radiators?
Methyl alcohol
Glycol
Nitrophenol
Nitrophenol
The reaction of phenol with chloroform in the presence of dilute sodium hydroxide finally introduces, which one of the following functional group?
-CH2Cl
-COOH
-CHCl2
-CHCl2
Given are cyclohexanol (I), acetic acid (II), 2,4,6-trinitropenol (III) and phenol (IV). In these, the order of decreasing acidic character will be
III > II> IV> I
II > III> I > IV
II > III> IV> I
II > III> IV> I
A.
III > II> IV> I
Higher the tendency to give a proton, higher is the acidic character, and tendency to lose a proton depends upon the stability of intermediate, ie, carbanion formed.
2,4,6 - trinitrophenol after the loss of a proton gives 2,4,6 -trinitrophenoxide ion which is stabilised by resonance -I effect and -M effect thus a most acidic among the given compounds. Phenol after losing a proton form phenoxide ion which is also stabilised by resonance, -M and -I effects but is less stabilised as compared to 2,4,6 trinitrophenoxide ions. Thus, it is less acidic as compared to 2,4,6 trinitrophenol. (CH3COOH) after losing a proton give acetate CH3OO- ion which is stabilised by only resonance. However, it is more resonance stabilised as compared to a phenoxide ion, thus more acidic as compared to phenol. 2,4,6 tri-nitrophenol, however, is more acidic than acetic acid due to the presence of three electron withdrawing - NO2 groups. cyclohexanol gives an anion that is least stable among the given, thus, it is least acidic.
Hence, the correct order of acidic strength is 2,4,6 -trinitrophenol > acetic acid > phenol > cyclohexanol
III> II> IV> I
Among the following four compounds
A) Phenol
B) Methyl Phenol
C) meta - nitrophenol
D) para-nitrophenol
the acidity order is
D > C > A > B
C > D > A> B
A > D > C > B
A > D > C > B
Consider the following reaction,
the product,Z,is
toluene
benzaldehyde
benzoic acid
benzoic acid
Switch
