Which of the following compounds has the highest boiling point?

Explain the mechanism of a unimolecular nucleophilic substitution $(S_N1)$ reaction with a suitable example.

In $S_N1$ reaction, the alkyl halide that on hydrolysis produces a racemic mixture is

The compound $CH_3-C(OH)(CH_3)-CCl_3$ is:

Consider the following anions:
$(I)$ $CF_3SO_3^-$
$(II)$ $C_6H_5SO_3^-$
$(III)$ $C_6H_5O^-$
$(IV)$ $CH_3COO^-$
When attached to $sp^3$ hybridized carbon,their leaving group ability in nucleophilic substitution reaction decreases in the order:

Which of the following undergoes $S_N1$ reaction at the fastest rate?