Vicinal and geminal dihalides can be distinguished by using:

What is the principal product of the following reaction?
$CH_3-CH(Br)-CH_2-CH_2-CH(Cl)-CH_3 + NaN_3 \rightarrow \text{Product}$

The reaction $Ph-CH_2-CH(F)-CH_3 \xrightarrow[EtOH]{KOH} X$. What is $X$?

Which of the following is most reactive towards nucleophilic substitution reaction?

$A$ $(C_{4}H_{8}Cl_{2})$ $\xrightarrow{\text{Hydrolysis at } 373 \text{ K}}$ $B$ $(C_{4}H_{8}O)$
$B$ reacts with hydroxylamine but does not give Tollen's test. Identify $A$ and $B$.

$2-$bromopentane is heated with potassium ethoxide in ethanol. The major product is