Most reactive for $S_{N}1$ reaction is

The reaction of $1$-chlorobutane with alcoholic potash gives $......$.

Discuss the relationship between nucleophilic substitution reactions and optical activity.

Which of the following compounds will form a precipitate most readily with $AgNO_3$?

For each of the following pairs of $E_2$ reactions,select the one that occurs with the greater rate constant:
$(1)$ $CH_3-CH_2-CH_2-Cl + CH_3-C(CH_3)_2-O^-$
$(2)$ $CH_3-CH_2-CH_2-I + CH_3-C(CH_3)_2-O^-$
$(3)$ $CH_3-CH(Br)-CH_3 + CH_3-O^-$
$(4)$ $CH_3-CH(Br)-CH_3 + CH_3-S^-$
$(5)$ $Ph-CH_2-CH(Br)-CH_2-CH_3 + OH^-$
$(6)$ $Ph-CH_2-CH_2-CH(Br)-CH_3 + OH^-$

In the given reaction,what is $A$?
$4-methylcyclohexyl bromide + OH^- \xrightarrow{S_N2} A$