Acetophenone when reacted with a base, C ₂ H ₅ ONa , yields a stable compound which has the structure

Step-by-step solution

Key Idea : Aldehydes or ketones with -H atom, in presence of dilute base, undergoes aldol condensation to give -hydroxy aldehyde or -hydroxy ketone. On heating, aldols eliminate water molecule to form , -unsaturated compound. Note: When aldehydes condense with ketones, it is the H of ketone which takes part in condensation. This reaction is called crossed aldol condensation.