Which statements about substitution reactions are correct?

I. The reaction between sodium hydroxide and 1-chloropentane predominantly follows an ${\mathrm{S}}_{\mathrm{N}}2$ mechanism.

II. The reaction between sodium hydroxide and 2-chloro-2-methylbutane predominantly follows an ${\mathrm{S}}_{\mathrm{N}}2$ mechanism.

III. The reaction of sodium hydroxide with 1-chloropentane occurs at a slower rate than with 1-bromopentane.

Which two molecules in given figure are cis–trans isomers of each other?

Halogenoalkanes can undergo substitution reactions with potassium hydroxide solution.

State an equation for the reaction of ${\mathrm{C}}_4{\mathrm{H}}_9\mathrm{Cl}$ with $\mathrm{KOH}$.

Substitution reactions may occur by either of two mechanisms namely ${\mathrm{S}}_{\mathrm{N}}1$ or ${\mathrm{S}}_{\mathrm{N}}2$. Outline the meaning of the term ${\mathrm{S}}_{\mathrm{N}}1$.

Predict the mechanism $\left({\mathrm{S}}_{\mathrm{N}}1 \mathrm{or} {\mathrm{S}}_{\mathrm{N}}2\right)$ expected for the reaction of the following halogenoalkanes with aqueous $\mathrm{KOH}$.

• 1-chlorobutane to form butan-1-ol
• 2-chloro-2-methylpropane to form 2-methylpropan-2-ol.

Explain the mechanism of each of the following reactions using curly arrows to represent the movement of electron pairs.

• 1-chlorobutane to form butan-1-ol
• 2-chloro-2-methylpropane to form 2-methylpropan-2-ol.

There are several structural isomers with the molecular formula ${\mathrm{C}}_5{\mathrm{H}}_{11}\mathrm{Br}$.

Deduce the name of one of the isomers which can exist as enantiomers and draw three-dimensional representations of its two enantiomers.