- Aqueous KOH favors nucleophilic substitution (SN1/SN2) reactions, where OH− acts as a nucleophile, forming alcohols.
- Alcoholic KOH, due to the presence of alkoxide ions (RO−), is a stronger base and favors the elimination (E2) reaction, leading to alkene formation.
A student is given one compound among the following compounds that gives positive test with Tollen's reagent. The compound is: 
Observe the following reaction and same reaction is carried out with the following compound: 
X and Y can be differentiated by:


