Experiment 27: Saponification reaction

 

Objective

• To study Saponification reaction

Materials required:

• Dil. Sodium hydroxide solution
• vegetable oil such as castor/ coconut oil (25 mL)
• common salt (about 10 g)
• beakers (50 mL)
• test tubes

Procedure

• Take about 10 mL of coconut oil in a beaker
• Add 15 mL of sodium hydroxide in the beaker (It is exothermic reaction)
• Add 5 g of common salt to this mixture and using a glass rod to stir the mixture continuously till the soap begins to set.
• Leave it for a day till the mixture cools and becomes solid.
• Filter the mixture to separate out the soap
• Remove the soap cake and cut it into desired shapes and sizes

Observations and Findings:

• Does it smell like any soap that you have used?
• Wash your hands with your soap. Does it lather like regular soap?
• Does it clean your hands as well as regular soap? Explain.

Conclusions:

• Heat is liberated during saponification

Theory:

• Oil or fat when treated with sodium hydroxide solution, gets converted into sodium salt of fatty acid (soap) and glycerol. This reaction is known as saponification.