Which of the following compounds has the lowest boiling point?

Which of the following reactions will give Hoffmann alkene as a major product?

$R-X + NaNO_2 \to P + NaX$
$R-X + AgNO_2 \to Q + AgX$
$P$ and $Q$ are related as

Arrange the following three chlorides in decreasing order of their reactivity towards $S_{N^1}$ reaction.

Which reaction results in the formation of a pair of enantiomers?

The rate-limiting step of an $S_N1$ reaction follows the sequence shown below. Based on the assumption that $R$ contains $3$ different groups,which statement is true?
$\mathop R\limits^{\delta \oplus } \,\mathop {Br}\limits^{\delta \Theta } \, \rightleftharpoons \,\mathop {\boxed{{R^ \oplus }Br^\Theta }}\limits_{(a)} \,\,\, \rightleftharpoons \,\mathop {\boxed{{R^ \oplus }}\,\boxed{Br^\Theta }\,}\limits_{(b)} \,\, \rightleftharpoons $ ${\boxed{{R^ \oplus }}}$ $ + $ $\mathop {\,\boxed{Br^\Theta }\,}\limits_{(c)} \,$