Following my last article about the chemistry of soap, I have become interested in making my own soap. From my research I have put together a practical/experiment that can be used in science lessons for students to make their own soap. The available scents with this recipe are coconut and cocoa. You can of course also try this yourself if you want to make some nice christmas presents.

The experiment works via the saponification reaction between fats from vegetable oils and sodium hydroxide from lye. The students will learn about saponification, how soaps work and how they can be made industrially.

1. Introduction

Humans have been been making and using soap for at least 2300 years. In all that time the manufacturing process has not changed much. Fats from animals or plants are reacted with sodium hydroxide in a reaction called saponification where soap is produced and glycerol is a…