291.
The order of stability of the following tautomeric compound is
A
I > II > III
B
III > II > I
C
II > I > III
D
II > III > I
Answer :
III > II > I
292.
The correct order of heats of combustion of above compounds is :
A
I > II > III
B
II > I > III
C
III > II > I
D
III > I > II
Answer :
III > II > I
293.
In the following groups
$$\eqalign{
& \mathop { - OAc}\limits_{\left( {\text{i}} \right)} \cr
& \mathop { - OMe}\limits_{\left( {{\text{ii}}} \right)} \cr
& \mathop { - OS{O_2}Me}\limits_{\left( {{\text{iii}}} \right)} \cr
& \mathop { - OS{O_2}C{F_3}}\limits_{\left( {{\text{iv}}} \right)} \cr} $$
the order of leaving group ability is
A
(i) > (ii) > (iii) > (iv)
B
(iv) > (iii) > (i) > (ii)
C
(iii) > (ii) > (i) > (iv)
D
(ii) > (iii) > (iv) > (i)
Answer :
(iv) > (iii) > (i) > (ii)
295. In which of the following species hyperconjugation is possible?
A
$$C{H_3} - C{H_2}$$
B
$${C_6}{H_5} - C{H_3}$$
C
$$C{H_2} = C{H_2}$$
D
\[C{{H}_{3}}\underset{\begin{smallmatrix}
| \\
\,\,\,\,C{{H}_{3}}
\end{smallmatrix}}{\overset{\begin{smallmatrix}
\,\,\,\,\,C{{H}_{3}} \\
|
\end{smallmatrix}}{\mathop{-C-}}}\,CH=C{{H}_{2}}\]
Answer :
$${C_6}{H_5} - C{H_3}$$
296.
Match the column I with column II in which formula for estimation of an element is given and mark the appropriate choice.
Column I
Column II
a.
Estimation of carbon
1.
$$\frac{{80}}{{188}} \times \frac{{{w_l}}}{w} \times 100$$
b.
Estimation of nitrogen
2.
$$\frac{{62}}{{222}} \times \frac{{{w_l}}}{w} \times 100$$
c.
Estimation of bromine
3.
$$\frac{{32}}{{233}} \times \frac{{{w_l}}}{w} \times 100$$
d.
Estimation of sulphur
4.
$$\frac{{28}}{{22400}} \times \frac{V}{w} \times 100$$
e.
Estimation of phosphorus
5.
$$\frac{{12}}{{44}} \times \frac{{{w_l}}}{w} \times 100$$
A
a - 5, b - 2, c - 4, d - 1, e - 3
B
a - 5, b - 4, c - 1, d - 3, e - 2
C
a - 5, b - 4, c - 2, d - 1, e - 3
D
a - 4, b - 3, c - 1, d - 2, e - 5
Answer :
a - 5, b - 4, c - 1, d - 3, e - 2
297. Which of the following names of substituted benzene compounds is not correct?
A
B
C
D
Answer :
298.
Match the compounds given in column I with the IUPAC names given in column II and mark the appropriate choice.
A
A - ii, B - i, C - iii, D - iv
B
A - iv, B - ii, C - i, D - iii
C
A - i, B - iii, C - ii, D - iv
D
A - iii, B - iv, C - ii, D - i
Answer :
A - iii, B - iv, C - ii, D - i
299. Which one of the following compounds is resistant to nucleophilic attack by hydroxyl ions?
A
Methyl acetate
B
Acetonitrile
C
Dimethyl ether
D
Acetamide
Answer :
Dimethyl ether
