What happpens when :
(i) `CH_(3)-CI` is treated with aqueous KOH?
(ii) `CH_(3)-CI` is treated with KCN ?
(iii) `CH_(3)-Br` is treated with Mg in the presence of dry ether ?

Explanation

Let's break down the question step by step:

### (i) When `CH₃Cl` is treated with aqueous KOH:

1. **Identify the Reactants**: The reactants are methyl chloride (`CH₃Cl`) and aqueous potassium hydroxide (`KOH`).

2. **Determine the Reaction Type**: The reaction is a nucleophilic substitution reaction (SN2 mechanism) because `KOH` provides hydroxide ions (`OH⁻`), which act as a nucleophile.

...