In the given esterification reaction,the labelled $^{18}O$ will be found in:

$A$ $\xleftarrow{CH_3OH, CH_3O^{-}}$ ($1$-methyl$-6-$oxabicyclo[$3.1$.$0$]hexane) $\xrightarrow{CH_3OH, H_2SO_4}$ $B$
$A$ $\&$ $B$ are :

Assertion: $tert$-Butyl methyl ether is not prepared by the reaction of $tert$-butyl bromide with sodium methoxide.
Reason: Sodium methoxide is a strong nucleophile.

Arrange the following sets of compounds in order of their increasing boiling points:
$(a)$ Pentan$-1-$ol,butan$-1-$ol,butan$-2-$ol,ethanol,propan$-1-$ol,methanol.
$(b)$ Pentan$-1-$ol,$n-$butane,pentanal,ethoxyethane.

Cyclohexanol and phenol can be distinguished by

Match the structures in Column-$I$ with their common names in Column-$II$ and $\text{IUPAC}$ names in Column-$III$.

Column-$I$	Column-$II$ (Common Name)	Column-$III$ ($\text{IUPAC}$ Name)
$(A)$ Phenol	$(1)$ Resorcinol	$(i)$ Benzene$-1,2-$diol
$(B)$ Benzene$-1,3-$diol	$(2)$ Catechol	(ii) Phenol
$(C)$ Benzene$-1,2-$diol	$(3)$ Phenol	(iii) Benzene$-1,4-$diol
$(D)$ Benzene$-1,4-$diol	$(4)$ Hydroquinone	(iv) Benzene$-1,3-$diol