Method of preparation of alkyl halide
$2\text{R-Br} + \text{Hg}_2\text{F}_2 \rightarrow 2\text{R-F} + \text{Hg}_2\text{Br}_2$
This reaction is known as

Which of following on oxidation forms propanone?

Identify the name of reaction when phenol reacts with chloroform in aqueous NaOH.

Which of the following compounds is obtained by Williamson synthesis ?