EXPERIMENT 1 SAPONIFICATION REACTION OF FAT: SOAP PRODUCTION
1.0 Objective
The objective of this experiments was to synthesize a sample of hard soap
To produce soap via the saponification reaction of fatty acids.
To test the soap produced.
2.0 Summary The chemical reaction of fat towards soap production which is soap are produced during the chemical reaction known as saponification also known as basic hydrolysis. The saponification number indicate the number indicate the number of fatty acid chain length of triglycerides. In this experiment there are three steps of analysis data done to relate with the objective, to synthesize a sample of hard soap and tested the soap produced. The triglycerides fats are hydrolyzed into free fatty acids then it’s combined with alkali to form a soap. The product of hydrolysis was mixed together with the usage of calcium chloride, about 0.8ml of foam form on above of cloudy solution and white precipitate was formed at the below of the solution also about o.4ml of white with a little yellow precipitate form above the graduated cylinder and below turns to cloudy mixtures when trisodium phosphate added inside the solution. The soap does not react with water because it’s contain cation Ca2+ while trisodium phosphate helps to soften and prevent soap molecules from reacting with Ca2+.
3.0 Introduction: The purpose of this experiment was to identify the chemical reaction of fat towards soap production which is soap are produced during the chemical reaction known as saponification also known as basic hydrolysis. Which is, in this procedure the hydrolysis of a fat under basic condition to form an alcohol and the salt of a carboxylic acid. This chemical reaction converts a fatty acid (triglycerides) and an alkali (sodium hydroxide) into soap when combination occur within a specific temperature range. Heat Fat + base
glycerol + salt (soap)
The salt of fatty acid called as a soap. Fatty acids found as free molecules but mostly often a part of triglyceride, in which consist three carbon chain (glycerol) with a fatty acid bonded to each three carbon atoms in the glycerol. The bond between the fatty acid and the glycerol is referred as ester linkage and in saponification process to form glycerol and soap, the ester linkage is broken to form this process.
4.0 Materials and Methodology 4.1 Materials: Chemical a) NaOH b) 95% ethanol c) Fat d) 50% water/ ethanol mixture NaCl e) 4% calcium chloride solution f) Trisodium phosphate
Apparatus a) Conical Flasks b) Beaker c) Filter Funnel d) Hirsch/ Buchner Funnel e) Watch glass f) Measuring cylinder
5.0 Result and discussion 5.1 Results Conditions
1.
Observations/ Explanation
Soap + 3mL distilled water
1.5 of white foam appears.
2.
Mixture from No 1. + 5 to 10 drops of 4% calcium chloride 0.8ml of foam form on above of cloudy solution. White precipitate was formed at the below of the solution.
3.
Mixture from No 2. + 0.5 g trisodium phosphate O.4ml of white with a little yellow precipitate form above the graduated cylinder and below turns to cloudy mixtures.
5.2 Discussion: The objective of the experiment was to synthesize a sample of hard soap and to test soap have produced. Saponification usually used to refer the reaction of metallic alkali (base) with a fat or oil to form soap. Based on the experiment done, saponification (hydrolysis) is an ester under basic condition to form an alcohol and the salt of carboxylic acid. The triglycerides process was reacted with a sodium hydroxide to produce glycerol and fatty acid salts. The alkaline solution, which is often called lye refers almost exclusively to soaps made with sodium hydroxide, brings the saponification reaction. In this reaction, the triglyceride fats are first hydrolyzed into free fatty acids, and then these combine with the alkali to form crude soap, an amalgam of various soap salts, fat or alkali, water, and liberated glycerol (glycerin) which is glycerin is useful for soap production and softening agent. When soap mixed with distilled water white foam appears top of the solution. The sodium and potassium salts of most carboxylic acids are water soluble. However, the calcium, magnesium, and iron salts are not. Thus, when soaps are placed in hard water that contains such ions, an insoluble, curdy solid forms. This process removes soap ions from solution, and decreases the cleaning effectiveness of soaps. After that, the solution foam form on above of cloudy solution and white precipitate was formed at the below of the solution. As explain, soap does not react excellently as it does not work well in hard water because it contain the solution of cation Ca2+. For the 3rd mixture, the trisodium phosphate was added and white with a little yellow precipitate form above the graduated cylinder and below turns to cloudy mixtures. This reaction occur as trisodium phosphate act as water softner.
I found that, chemical substances was those can be converted into soap. CH2-OOC-R - CH-OOC-R - CH2-OOC-R (fat) + 3 NaOH (or KOH) Heated CH2-OH -CH-OH - CH2-OH (glycerol) + 3 R-CO2-Na (soap) R= (CH2)14CH3 (right) The additive of sodium hydroxide (NaOH) in this experiment caused the hard soap formed. Whereas potassium soap (potassium hydroxide (KOH)) tends to be softer than the corresponding sodium soap. Vegetable oils and animal fats are fatty esters in the form of triglycerides. The alkali breaks the ester bond and releases the fatty acid and glycerol. If necessary, soaps may be precipitated by salting it out with saturated sodium chloride.
4.2 Methodology:
6.0 Conclusion: Based on the experiment done, the objective of the experiment was successfully achieved to synthesize a sample of hard soap and to test soap produced. From the experiment defined that saponification is hydrolysis of an ester under basic condition to form an alcohol and the salt of carboxylic acid which hydrolysis of the ester linkages between fatty acids and glycerol. From the mixture number 2, after the mixture was shaken, foam form on above of cloudy solution and white precipitate was formed at the below of the solution. This is because, soap does not react excellently as it does not work well in hard water as it contain the solution of cation Ca2+.
From the second
mixture, the solution was mixed with trisodium phosphate and white with a little yellow precipitate form above the graduated cylinder and below turns to cloudy mixtures. This reaction occur as trisodium phosphate act as water softner. It helps to prevent soap molecule from reacting with CA2+ ion so the cleaning process will not affected. Based on this experiment, the objective was successfully achieved. To obtain a good result, during the preparation of NaOH, we need to make sure that the sodium hydroxide was dissolved so there is no granules left during experiment.
7.0 Tutorial 7.1 Pre Laboratory Question 1. Saponification means the hydrolysis of the ester linkages between fatty acids and glycerol. 2. Soaps (sodium or potassium fatty acids salt) produced by hydrolysis reaction acts as excellent cleanser because of its ability to act as an emulsifying agent. The emulsifying agent are capable of dispersing one liquid to another immiscible liquid, means that while oil (which attracts dirt) doesn’t naturally mix with water, so that soap can remove oil and dirt in such a way that it can be removed. 3. Synthetic detergent is petroleum byproducts, it can provide more cleaning power, able to break up oil droplets and making them very useful for cleaning clothes from grease stains. It also can be used in hard water, in a acidic solution, and more soluble in water than soaps while in laundry purposes, its acts as softener and surfactants. 7.1 Post Laboratory Question 1. The nature of soaps depends on alkali metal, which the soap that are produced from sodium hydroxide was firmer while potassium hydroxide are softer. When Sodium Hydroxide (NaOH) is replaced by Potassium hydroxide (KOH) long chain carboxyclic acid will form. This means it will formed a soft soap.
8.0 References
LAB REPORT LIPID in 2013. Available from http://www.slideshare.net/UmiBiee/labreport-lipid.
J. Chem. Educ. Soap and glycerol, Chemical Education, pages 172, 2013.
T.Y Toon, S. Shanmuganathan, Oxford Fajar, Chemistry for matriculation, Fourth Edition 2013.
Isah,A G. (2006). Production of Detergent from Castor oil. Leornado Journal of Practices and Technologies 9: 153-160
