Making soaps and detergents using castor oil

Two clusters of white soap or detergent bubbles on a flat surface against a turquoise background

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Try this class practical to make a soap or detergent using castor oil and either sodium hydroxide or sulfuric acid. Includes kit list and safety instructions.

Castor oil is used as a source of vegetable oils which, on reaction with warm concentrated alkali, form soaps. The vegetable oils in castor oil also contain hydroxy-groups (–OH) which will react readily with concentrated sulfuric acid, forming a long chain molecule with an ionic sulfonate group on the end.

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