The compound added to prevent chloroform from forming phosgene gas is

The reaction of $n$-propyl bromide with ethanolic potassium hydroxide $(KOH)$ produces ...... .

Which compound gives acetaldehyde upon reaction with aqueous $KOH$?

Explain why:
$(i)$ the dipole moment of chlorobenzene is lower than that of cyclohexyl chloride?
$(ii)$ alkyl halides,though polar,are immiscible with water?
$(iii)$ Grignard reagents should be prepared under anhydrous conditions?

Which of the following nucleophiles will show minimum reactivity towards $S_N2$ reaction:

In the given reaction:
$CH_3-CH_2-\ddot{S}-CH_2^*-CH_2-Br \xrightarrow{HOH} [X]$
$[X]$ will be: