The total number of hydrogen atoms in product $A$ and product $B$ is $ . . . . . . $.

Explain two differences between haloalkanes and haloarenes.

Correct statements regarding alkyl halides ($R-X$) among the following are: A. Alcohol being less polar solvent as compared to water, alcoholic $KOH$ favours elimination reaction with $R-X$. B. Order of reactivity towards $S_N1$ mechanism is $C_6H_5-CH_2-Cl > C_6H_5-CHCl-C_6H_5$. C. Non substituted aryl halides exhibit properties similar to alkyl halides. D. Vinyl chloride is an example of haloalkene and allyl chloride is an example of haloalkyne. E. $R-Cl$ can be prepared by reacting $R-OH$ with $SOCl_2$ but $Ar-Cl$ cannot be prepared by reacting $Ar-OH$ with $SOCl_2$. Choose the correct answer from the options given below:

The given product cannot be obtained in the above reaction. Identify the correct product obtained.

The correct order of increasing reactivity of $C-X$ bond towards nucleophile in the following compounds is:
$I$: Chlorobenzene (or aryl halide)
$II$: $2,4$-Dinitrochlorobenzene
$III$: $(CH_3)_3C-X$ ($3^o$ alkyl halide)
$IV$: $(CH_3)_2CH-X$ ($2^o$ alkyl halide)

In the following reaction sequence,$X$ and $Z$,respectively,are:
$CH_{3}CH_{2}CH_{2}-OH + PCl_{5} \rightarrow CH_{3}CH_{2}CH_{2}Cl + X + HCl$
$CH_{3}CH_{2}CH_{2}Cl \xrightarrow{alc. KOH, \Delta} Y$
$Y \xrightarrow{HBr, (C_{6}H_{5}CO)_{2}O_{2}} Z$