The rate of reaction of $t-$butyl bromide and $NaOH$ in water depends on the concentration of

Which of the following alkyl halides is most reactive towards the $S_{N}1$ mechanism?

Arrange the compounds of each set in order of reactivity towards $S_{N}2$ displacement:
$(i)$ $2-Bromo-2-methylbutane$,$1-Bromopentane$,$2-Bromopentane$
$(ii)$ $1-Bromo-3-methylbutane$,$2-Bromo-2-methylbutane$,$2-Bromo-3-methylbutane$
$(iii)$ $1-Bromobutane$,$1-Bromo-2,2-dimethylpropane$,$1-Bromo-2-methylbutane$,$1-Bromo-3-methylbutane$.

The graph which represents the following reaction is :
$(C_6H_5)_3C-Cl \xrightarrow{OH^{-} / \text{Pyridine}} (C_6H_5)_3C-OH$

Which one of the following compounds will give a $Saytzeff$ alkene as the major product in an elimination reaction?

Select the correct decreasing order of boiling points of compounds from the following.