The halogen exchange reaction among the following is exhibited by:  

1.	\(\begin{aligned}RX \ + \ NaI \ \xrightarrow[]{\textbf{Acetone}} \ RI \ + \ NaX \\ \\ \end{aligned} \)
2.
3.
4.

Consider the reactions:

\(C_6H_5CH_2Br \xrightarrow[2.~H_3O^+] {1.Mg,Ether}~\mathrm X, \)
The product 'X' in the above reaction is:
1. \(\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{OH} \)
2. \(\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_3 \)
3. \(\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{CH}_2 \mathrm{C}_6 \mathrm{H}_5 \)
4. \(\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{OCH}_2 \mathrm{C}_6 \mathrm{H}_5\)

Why is the Wurtz reaction not preferred for the preparation of alkanes containing an odd number of carbon atoms?

The correct sequence for increasing dipole moment is:

1. CCl₄ < CHCl₃ < CH₂Cl₂
2. CHCl₃ < CH₂Cl₂ < CCl₄
3. CCl₄ < CH₂Cl₂ < CHCl₃
4. CH₂Cl₂ < CCl₄ < CHCl₃

A hydrocarbon C₅H₁₀ does not react with chlorine in the dark but gives a single monochloro compound C₅H₉Cl in bright sunlight. Hydrocarbon could be:

The compound with the formula C₄H₉Br has how many structural isomers?

a. CH₃Br or CH₃I  
b. (CH₃)₃CCl or CH₃Cl
The above-mentioned compounds that react faster in S N₂ reaction with OH^- from each given pair respectively are:

1. CH₃Br, CH₃I
2. CH₃Br, (CH₃)₃CCl
3. CH₃I, CH₃Cl
4. CH₃I, (CH₃)₃CCl

Out of ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{CH}}_2\mathrm{Cl}$ $\mathrm{and}$ ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{CHClC}}_6{\mathrm{H}}_5$, the one that gets easily hydrolyzed by aqueous KOH is :

1. ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{CHClC}}_6{\mathrm{H}}_5$ 

2. ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{CH}}_2\mathrm{Cl}$

3. Both react equally

4. None of the above

p-Dichlorobenzene has a higher melting point than those of o- and m-isomers because :