Aldol condensation - Aldehydes and Ketones

(a) This reaction occurs between two molecules of carbonyl compounds; one molecule should have at least two α-hydrogen sets. In that reaction best result is taken while

Both molecule are similar or

One could comprise no α-hydrogen molecule and other should have as a minimum two α-hydrogens.

(b) These reactions are execute while base is NaOH and reaction temperature is high (> 100°).

(c) The another reaction is two step reaction. First step is aldol creation and second step is dehydration of aldol.