MCQ
The quantitative estimation of $O_3$ is based on
- ✓Its reaction with $PbS$
- BIts reaction with $NO$
- CIts reaction with $KI$ and titration of $I_2$ liberated with sodium thiosulphate
- DIts reaction with $H_2O_2$ in presence of $K_2Cr_2O_7$
$\Rightarrow S > Se > Te > O$
(Oxygen shows least electron gain enthalpy due to small size of atom)
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$(I)$ They have high melting points, higher than those of pure metals
$(II)$ They are very hard
$(III)$ They retain metallic conductivity
$(IV)$ They are chemically more reactive than the pure metals
$2$. $XeF_2 \xrightarrow{H_2O} $
$3$. $XeF_4 \xrightarrow{H_2O} $
$4$. $PbO_2 \xrightarrow{\Delta } $
$5$. $XeF_6 \xrightarrow{H_2O} $
In how many of the above processes, $O_2$ will be one of the products
| $column 1$ | $column 2$ | $column 3$ |
| $(I)$ Toluene | $(i)$ $\mathrm{NaOH} / \mathrm{Br}_2$ | $(P)$ Condensation |
| $(II)$ Acetophenone | $(ii)$ $\mathrm{Br}_2 / \mathrm{h} v$ | $(Q)$ Carboxylation |
| $(III)$ Benzaldehyde | $(iii)$ $\left(\mathrm{CH}_3 \mathrm{CO}\right)_2 \mathrm{O} / \mathrm{CH}_3 \mathrm{COOK}$ | $(R)$ Substion |
| $(IV)$ Phenol | $(iv)$ $\mathrm{NaOH} / \mathrm{CO}_2$ | $(S)$ Haloform |
($1$) For the synthesis of benzoic acid, the only $CORRECT$ combination is
$[A] (III) (iv) (R)$ $[B] (IV)(ii) (P)$ $[C] (I) (iv) (Q)$ $[D] (II) (i) (S)$
($2$) The only CORRECT combination in which the reaction proceeds through radical mechanism is
$[A] (I)$ $(ii) (R)$ $[B] (II) (iii) (R)$ $[C] (III) (ii) (P)$ $[D] (IV) (i) (Q)$
($3$) The only CORRECT combination that gives two different carboxylic acids is
$[A] (IV) (iii) (Q)$ $[B] (III) (iii) (P)$ $[C] (II) (iv) (R)$ $[D] (I) (i) (S)$
Given the answer quetion ($1$) ($2$) and ($3$)