How Saponification Makes Soap - ThoughtCo
Aug 02, 2018·Hard Soap: Hard soap is made using sodium hydroxide (NaOH) or lye. Hard soaps are especially good cleansers in hard water that contains magnesium, chloride, and calcium ions. Soft Soap: Soft soap is made using potassium hydroxide (KOH) rather than sodium hydroxide. In addition to being softer, this type of soap has a lower melting point.