Write the chemical equations for the following reactions:
$(i)$ Reimer-Tiemann reaction
$(ii)$ Kolbe's reaction

(N/A) $(i)$ Reimer-Tiemann reaction:
In this reaction,the $-OH$ group is retained,and the reaction occurs at the ortho position. When phenol is heated with chloroform in the presence of sodium hydroxide,an aldehyde $(-CHO)$ group is introduced at the ortho position of the phenol,which is known as the Reimer-Tiemann reaction.
During this reaction,an intermediate substituted benzal chloride is formed,which undergoes hydrolysis in the presence of alkali $(NaOH)$ to form the product salicylaldehyde.
$(ii)$ Kolbe's reaction:
In this reaction,the $-OH$ group is retained,and $CO_2$ is attached at the ortho position. Phenol reacts with sodium hydroxide $(NaOH)$ to form sodium phenoxide.
The phenoxide ion is more reactive than phenol towards electrophilic aromatic substitution,so the phenoxide reacts with a weak electrophile like $CO_2$ to form the main product,ortho-hydroxybenzoic acid (salicylic acid).