About 'Alkali'

Any base or hydroxide eg: soda, potash etc that is soluble in water & can neutralise acids.Commonly used alkali's are Sodium hydroxide or caustic soda & Potassium hydroxide or caustic potash

What are Soaps?

Soaps are water soluble sodium or potassium salts of fatty acids. Soaps are made from fats & oils, or their fatty acids, by treating them chemically with a strong alkali.