201. Acetaldoxime reacts with \[{{P}_{2}}{{O}_{5}}\] to give
A
Methyl cyanide
B
Methyl cyanate
C
Ethyl cyanide
D
None of these
Answer :
Methyl cyanide
202.
Arrange the following amines in the decreasing order of basicity :
A
I > II > III
B
III > I > II
C
III > II > I
D
I > III > II
Answer :
III > I > II
is most basic as the lone pair of nitrogen is easily available for the donation.
lone pair is not involved in resonance but nitrogen atom is $$S{p^2}$$ hybridsed whereas in compound II the lone pair of nitrogen is involved in aromaticity which makes it least basic. 203. The reaction \[\overset{+\,\,\,}{\mathop{Ar{{N}_{2}}C{{l}^{-}}}}\,\xrightarrow{Cu/HCl}ArCl+{{N}_{2}}\] \[+\,CuCl\] is named as _________.
A
Sandmeyer reaction
B
Gatterman reaction
C
Claisen reaction
D
Carbylamine reaction
Answer :
Gatterman reaction
204. Which of the following has highest $$p{K_b}$$ value?
A
$${\left( {C{H_3}} \right)_3}CN{H_2}$$
B
$$N{H_3}$$
C
$${\left( {C{H_3}} \right)_2}NH$$
D
$$C{H_3}N{H_2}$$
Answer :
$$N{H_3}$$
205. For nitration of aniline, which of the following steps is followed?
A
Direct nitration using nitrating mixture $$\left( {{\text{conc}}{\text{.}}\,HN{O_3} + {\text{conc}}{\text{.}}\,{H_2}S{O_4}} \right)$$ followed by oxidation.
B
Using fuming $$HN{O_3}$$ carrying out reaction at $$273\,K$$ followed by hydrolysis.
C
Using $$NaN{O_2}$$ and $$HCl$$ followed by reaction with conc. $$HN{O_3}$$ followed by hydrolysis.
D
Acetylation followedby nitration and hydrolysis.
Answer :
Acetylation followedby nitration and hydrolysis.
206.
The correct increasing order of basic strength for the following compounds is
A
II < III < I
B
III < I < II
C
III < II < I
D
II < I < III
Answer :
II < I < III
207. Among the following amines, the strongest $${\rm{Br\ddot onsted}}$$ base is ________.
A
B
C
D
Answer :
is the strongest $${\rm{Br\ddot onsted}}$$ base as there is no delocalisation of lone pair of electrons of $$N$$ atom which is possible in aniline and in pyrrole. 208. The most basic amine among the following is
A
B
C
D
Answer :
209.
The product – $$(C)$$ obtained in the following sequence of reactions is
\[\xrightarrow[\left( 2 \right)\,CuCl]{\left( 1 \right)\,HONO}A\xrightarrow{Sn/HCl}B\xrightarrow[\left( 2 \right)\,{{H}_{3}}P{{O}_{2}}]{\left( 1 \right)\,HONO}C\]
A
B
C
D
Answer :
210.
\[{{C}_{6}}{{H}_{5}}N{{O}_{2}}\xrightarrow{Sn/HCl}P\xrightarrow[HCl]{NaN{{O}_{2}}}\] \[Q\xrightarrow[\Delta ]{HB{{F}_{4}}}R\]
The end product $$R$$ in the given sequence of reactions is
A
benzoic acid
B
fluorobenzene
C
phenol
D
chlorobenzene
Answer :
fluorobenzene