101. What is the carbon-carbon bond length in benzene?
A
$$1.20\,\mathop {\text{A}}\limits^{\text{o}} {\text{ and 1}}{\text{.31}}\,\mathop {\text{A}}\limits^{\text{o}} $$
B
$$1.39\,\mathop {\text{A}}\limits^{\text{o}} $$
C
$$1.39\,\mathop {\text{A}}\limits^{\text{o}} {\text{ and }}1.20\,\mathop {\text{A}}\limits^{\text{o}} $$
D
$$1.20\,\mathop {\text{A}}\limits^{\text{o}} $$
Answer :
$$1.39\,\mathop {\text{A}}\limits^{\text{o}} $$
102.
Choose the correct alkyne and reagents for the preparation of 
A
\[,HgS{{O}_{4}},{{H}_{2}}S{{O}_{4}},{{H}_{2}}O\]
\[,HgS{{O}_{4}},{{H}_{2}}S{{O}_{4}},{{H}_{2}}O\] B
\[,HgS{{O}_{4}},{{H}_{2}}S{{O}_{4}},{{H}_{2}}O\]
\[,HgS{{O}_{4}},{{H}_{2}}S{{O}_{4}},{{H}_{2}}O\] C
\[,B{{H}_{3}},{{H}_{2}}{{O}_{2}},NaOH\]
\[,B{{H}_{3}},{{H}_{2}}{{O}_{2}},NaOH\] D
\[,B{{H}_{3}},{{H}_{2}}{{O}_{2}},NaOH\]
\[,B{{H}_{3}},{{H}_{2}}{{O}_{2}},NaOH\]
Answer :
\[,HgS{{O}_{4}},{{H}_{2}}S{{O}_{4}},{{H}_{2}}O\]
\[,HgS{{O}_{4}},{{H}_{2}}S{{O}_{4}},{{H}_{2}}O\] 
103. Which one of these, is not compatible with arenes?
A
Greater stability
B
Delocalisation of $$\pi $$ -electrons
C
Electrophilic additions
D
Resonance
Answer :
Electrophilic additions
104. The correct trend of acidic nature of the following alkynes is
A
$$CH \equiv CH > C{H_3} - C \equiv $$ $$CH > C{H_3}C \equiv CC{H_3}$$
B
$$C{H_3} - C \equiv CH > CH \equiv $$ $$CH > C{H_3}C \equiv CC{H_3}$$
C
$$C{H_3}C \equiv CC{H_3} > C{H_3} - C \equiv $$ $$CH > CH \equiv CH$$
D
$$CH \equiv CH > C{H_3}C \equiv $$ $$CC{H_3} > C{H_3}C \equiv CH$$
Answer :
$$CH \equiv CH > C{H_3} - C \equiv $$ $$CH > C{H_3}C \equiv CC{H_3}$$
105. Toluene reacts with excess of $$C{l_2}$$ in presence of sun light to give a product which on hydrolysis by reaction with $$NaOH$$ gives
A
B
C
D
Answer :
106. Which of the following molecules is least resonance stabilized ?
A
B
C
D
Answer :
is non-aromatic and hence least resonance
107.
The major product of the following reaction is :
\[C{{H}_{3}}C\equiv CH\xrightarrow[\left( \text{ii} \right)\,\,Dl]{\left( \text{i} \right)\,\,DCl\text{(lequiv}\text{.)}}\]
A
\[C{{H}_{3}}CD\left( I \right)CHD\left( Cl \right)\]
B
\[C{{H}_{3}}CD\left( Cl \right)CHD\left( I \right)\]
C
\[C{{H}_{3}}C{{D}_{2}}CH\left( Cl \right)\left( I \right)\]
D
\[C{{H}_{3}}C\left( I \right)\left( Cl \right)CH{{D}_{2}}\]
Answer :
\[C{{H}_{3}}C\left( I \right)\left( Cl \right)CH{{D}_{2}}\]
108.
Match the column I with column II and mark the appropriate choice.
| Column I | Column II | ||
|---|---|---|---|
| a. | $$n$$ - Butane $$ \to $$ 2 - Methylpropane | 1. | Free radical substitution |
| b. | \[C{{H}_{4}}+C{{l}_{2}}\xrightarrow{h\upsilon }C{{H}_{3}}Cl\] | 2. | Wurtz reaction |
| c. | $$RCOONa\, + $$ soda lime $$ \to RH$$ | 3. | Isomerisation |
| d. | \[RX+Na\xrightarrow{\text{ether}}R-R\] | 4. | Decarboxylation |
A
a - 3, b - 1, c - 4, d - 2
B
a - 2, b - 4, c - 1, d - 3
C
a - 1, b - 2, c - 4, d - 3
D
a - 4, b - 1, c - 3, d - 2
Answer :
a - 3, b - 1, c - 4, d - 2
109. A compound is treated with $$NaN{H_2}$$ to give sodium salt. Identify the compound.
A
$${C_2}{H_2}$$
B
$${C_6}{H_6}$$
C
$${C_2}{H_6}$$
D
$${C_2}{H_4}$$
Answer :
$${C_2}{H_2}$$
110. In preparation of alkene from alcohol using $$A{l_2}{O_3}$$ which is effective factor ?
A
Porosity of $$A{l_2}{O_3}$$
B
Temperature
C
Concentration
D
Surface area of $$A{l_2}{O_3}$$
Answer :
Surface area of $$A{l_2}{O_3}$$