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Abstract:
Saponification is an esterification process that is used to make so from the hydrolysis of fats and oils. This process have the glycerol molecule, and a sodium carboxylate salt in most case sodium stearate being formed, however this salt depends on the base being used. In the experiment 23ml of vegetable oil was mixed with 20ml of ethyl alcohol along with 20 ml of 25% sodium hydroxide in a 250-mL Erlenmeyer flask. The content was then heated on a water bath whilst gently mixing with a glass rod. After 20 minutes of heating the alcohol scent disappeared denoting the completion of the reaction with pasty mass comprising of soap, glycerol and excess sodium hydroxide. After this was done an ice bath was used to precipitate the soap along with 150ml of saturated sodium chloride solution, and vigorous mixing. By this the soap will float as the aqueous solution gets denser; this was then filtered using the vacuum suction, washed with 10ml ice water and the necessary observation taken. Saponification is a commercial process used to generate detergent by hydrolyzing fats and oils using sodium or potassium hydroxide in an esterification reaction. This process usually involved the production of glycerol and excess sodium hydroxide solutions as the byproducts. This product and procedure have proved to be an economical one and can be applied as it is easily attained.

Procedure:
23 mL of a vegetable oil was measured into a 250-mL Erlenmeyer flask. After which 20 mL of ethyl alcohol was added (to act as a solvent) along with 20 mL of 25% sodium hydroxide solution (25% NaOH). Whilst the flask with its contents is heated gently in a boiling water bath the mixture was constantly mixed using a glass rod. A 600-mL beaker containing about 200 mL of tap water and a few boiling chips was uses as a water bath. After being heated for about 20 minutes and the reaction came to completion the scent of the ethyl alcohol disappeared; this is an indication of the reaction’s culmination. A pasty mass containing a mixture of the soap, glycerol, and excess sodium hydroxide was obtained. Using an ice water bath the flask was cooled with its contents. 150 mL of a saturated sodium chloride was then added to precipitate or salt out the soap from the mixture with vigorous mixing. This process increased the density of the aqueous solution; as a result, soap floated out from the aqueous solution. The precipitated soap was filtered with the aid of suction and then washed with 10 mL of ice cold water. The appearance of the soap was also observed and the necessary observations recorded on the Report Sheet. Reagents Materials

Vegetable oilBeaker
NaOHHot plate, clamp stand
Ethyl alcoholConical flask
NaCl

Observation:
It was evident that when the vegetable oil was mixed ethyl alcohol and sodium hydroxide a pale yellow colour arrived. When this mixture was placed in a water bath small bubbles were seen on the top of the liquid, however it was placed on an ice bath and an amber colour was seen as the mixture emulsified. With the addition of sodium chloride the soap mixture gained density thus giving a yellow mixture.

Discussion:
Saponification is the process of making soaps; this involves the hydrolysis of the esters present in vegetables by reacting with sodium hydroxide and steam. However in this lab sodium hydroxide and ethyl alcohol were used. The process of saponification is an esterification method with a molecule of water being eliminated; sodium hydroxide or potassium hydroxide maybe used in such a reaction with an acid catalyst, base catalyst or alcohol. In the mechanism of saponification the vegetable oil and the aqueous sodium hydroxide is heated with steam. This hydrolysis yields propane-1,2,3-triol(glycerol) and salts of long chain carboxylic acids.

Sodium hydroxide is used instead of sodium chloride, since sodium chloride precipitated...
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