Write the structure of the following organic halogen compound:
1-Bromo-4-sec-butyl-2-methylbenzene

Which of the following has the highest dipole moment?

$\left(\mathrm{i}\right) {\mathrm{CH}}_2{\mathrm{Cl}}_2 \left(\mathrm{ii}\right) {\mathrm{CHCl}}_3 \left(\mathrm{iii}\right) {\mathrm{CCl}}_4$

Which compound in each of the following pair will react faster in ${\mathrm{S}}_{\mathrm{N}}2$ reaction with ${\mathrm{OH}}^{-}$?

$({\mathrm{CH}}_3{)}_3\mathrm{CCl} \mathrm{or} {\mathrm{CH}}_3\mathrm{Cl}$