ACKNOWLEDGEMENT In the accomplishment of this project successfully, many people have best owned upon me their blessings and the heart pledged support, this time I am utilizing to thank all the people who have been concerned with project. Primarily I would thank god for being able to complete this project with success. Then I would like to thank my principal N M ASOKAN Sir and chemistry teacher K C HUBBALLI Sir, whose valuable guidance has been the ones that helped me patch this project and make it full proof success.His suggestions and his instructions have served as the major contributor towards the completion of the project. Then I would like to thank my parents and friends who have helped me with their valuable suggestions and guidance has been helpful in various phases of the completion of the project. Last but not the least I would like to thank my classmates who have helped me a lot and also Sir Lab attendant FAKIRAPPA ANNA. -: CONTENTS :1. 2. 3. 4. 5. INTRODUCTION EXPERIMENT THEORY CONCLUSION BIBLIOGRAPHY PREPARATION OF SOAP GENERAL INFORMATION What Are Oils & Fats? Alcohol or alkanols may be considered as hydroxyl derivatives of saturated hydrocarbons or alkanes and represented by general formula R-OH group. All alcohols contain the hydroxyl group (-OH) as the functional group, which determine the general properties of the family. The remaining part, i.e., other than the (OH) group is called the hydrocarbon structure. Alcohols are classified as mono, di- and trihydric alcohols according to the number of hydroxyl groups contained in their molecules. Thus: C2H5OH CH2OH Ethyl Alcohol │ (Monohydric) CH2OH C2H4(OH)2 OR Glycol (Dihydric) CH2OH │ CH2OH OR C3H5(OH)3 │ CH2OH Glycerol (Trihydric) Glycerol is a trihydric alcohol with three hydroxyl groups. Carboxylic (or alkanoic) acids are the organic compounds containing carboxyl (–COOH) group. They are represented by the general formula R–COOH. Aliphatic monocarboxylic acids (containing one carboxyl group) are known as fatty acids because some of their higher members with long hydrocarbon chains are obtained from oils and fats. Members of family of carboxylic acids in which R contains 15 or more carbon atoms are known as higher fatty acids. Some common higher fatty acids are: C15H31COOH C17H35COOH C17H35COOH (Palmitic acid) (Oleic acid) (Stearic acid) Oils and fats are the triesters of glycerol with various long chain organic acids, both saturated and unsaturated. These triesters are usually known as glycerides. Oils are liquids at ordinary temperatures while fats are solids. The glycerides constituting oils contain a larger proportion of unsaturated acids, such as oleic acid (C17H33COOH), linoleic acid (C17H31COOH), etc., while the glycerides forming the fats contain a larger proportion of saturated acids, such as lauric acid (C11H23COOH), myristic acid (C13H27COOH), palmitic acid (C15H31COOH) and stearic acid (C17H35COOH). The glycerides are named according to the acid radical present in them. For instance, the glyceride containing stearic acid radical is called stearin or tristearin and the one containing the palmitic acid radical is named as palmitin or tripalmitin. CH2OOCC17H35 CH2OOOCC15H31 │ │CC15H31 │ │ CHOOCC17H35 CHO CH2OOCC17H35 CH2OOCC15H31 (Stearin or triesterin) (Palmitin or tripalmitin) Usually more than one acid radical is present in the same glyceride. These are called mixed glycerides. The naturally occurring oils and fats are generally mixtures of such ‘mixed glycerides’. For instance: CH2OOCC17H35 CH2OOCC15H31 │ │ CHOOCC15H31 CHOOCC17H35 │ │ CH2OOCC17H35 CH2OOCC17H35 (Oleo-palmito-stearin) (Palmito-distearin) CH2OOCC17H35 │ CHOOCC15H31 │ CH2OOCC15H31 (Stearo-dipalmitin) WHAT ARE SOAPS? Soaps are mixtures of sodium or potassium salts of higher fatty acids such as stearic acid, palmitic acid, oleic acid. They are usually obtained by the hydrolysis of oils and fats with sodium or potassium hydroxide (alkali hydrolysis). For example, CH2OOCC15H31 CH2OH │ │ CHOOCC15H31 + NaOH → (Sodium palmitate) CHOH │ │ CH2OOCC17H35 CH2OH (Dipalmito-stearin) 2C15H31COONa (Soap) C17H35COONa (Sodium Sterate) (Oil or fat) (Soap) The alkali hydrolysis of oil and fat is known as Saponification. The sodium soaps are generally hard in consistency and are known as Hard Soaps. The potassium soaps, on the other hand, are comparatively soft and more soluble and are referred to as Soft Soaps. Shaving creams, vanishing creams, shampoos, etc., are all potassium soaps CLEANSING ACTION OF SOAPS: Soaps act as cleansing agent by decreasing the surface tension of water. Any surface or interface has a surface tension, or surface energy caused by the unequal attraction, between molecules in opposite sides. A detergent (cleansing agent) ties together the two surfaces and consequently diminishes the fraction of dissimilar cohesive forces at the surface and hence decreases the surface energy. The adsorption of the detergent at the solid surface permits wetting of the surface by water and rolling up of oil films into small droplets. Cleansing (or washing) properties of soaps and detergents depend on the lowering they cause in the surface tension of water. Greater the lowering in the value of surface tension, greater will be the cleansing capacity of the detergent. Surface tension of two soap solutions ( counting the number of drops ( equal weights of the detergents. 1and / 1 2 2) = ) can be easily compared by 1and 2 formed from equal volumes containing / 1 2 Stalagmometer or Drop pipette: It is an apparatus used for comparing relative surface tension of liquids. It consists of a capillary tube the end of which is flattened out (in order to give a large dropping surface) and the surface is ground flat and polished. The capillary is sealed on to a tube of wider bore on which a bulb is blown and on the stem of the tube, two marks are etched, one above and another below the bulb. EXPERIMENT:OBJECTIVE: a) To prepare soap from oils (say Mahuwa oil, ground nut oil and coconut oil). b) To compare the soap prepared with the market soap by determining their foaming capacity and cleaning effect. APPARATUS: Beakers, Stalagmometer (drop pipette), test tubes, petri dishes, stop watch. CHEMICALS REQUIRED: The washing soap is prepared from the following chemicals: 1. 2. 3. 4. Mahuwa Oil Caustic Soda Starch Water = = = = 100g 25g 25g 150ml PROCEDURES: 1. Dissolve caustic soda in 150ml of water. This solution is called lye. Let this soda lye cool. 2. Warm the oil on flame and mix 50g of starch with it. Remove the flame and allow the oil to cool. 3. When the oil and soda lye are at about the same temperature (which can be tested by putting a finger in each of them at the same time). Add soda lye to the oil in a thin stream. 4. Stir the mass constantly well with a wooden rod till the whole lye has been added. A creamy pasty mass is obtained. 5. Stir the mass more till a semi-solid mass is obtained. Transfer it into an iron mould or a wooden frame. 6. Cover the mould or frame with wooden board or a gunny bag and leave it for few hours. 7. Remove the flame and take out the soda slab. Cut it with the help of a wire into cakes of desired size. NOTE: - Soaps from ground nut oil as well as coconut oil are prepared by same procedure. PRECAUTION: Caustic soda is very corrosive and should not, therefore, be touched with bare hands. COMPARISON OF THE FOAMING CAPACITIES OF THE TWO SOAP SAMPLES: 1. Take 0.1g of each soap sample in two test tubes numbered as 1 and 2. 2. Add 5ml of distilled water in each test tube and shake them vigorously for minutes preferably in a shaker. 3. Place the test tubes in a test tube stand and start the stop watch. 4. Note the time when the foam in each of the tubes disappears. 2-3 Foaming capacity of that soap sample will be greater in which case it takes longer time to disappear. FOAMING CAPACITY OF DIFFERENT SOAPS INTRODUCTION: Soaps and detergents are used for removing grease and dirt from our clothes. But all soaps are not equally effective in their cleansing action. Soaps are the sodium or potassium salts of higher fatty acids such as palmitic acid (C15H31COOH), stearic acid (C17H35COOH), oleic acid (C17H35COOH) etc.,their general formula being RCOONa or RCOOK where R is the longer chain alkyl group i.e. C15H31, C17H33 etc., thus, each soap molecule consists of two parts a lipophilic (oil soluble) part R and a hydrophilic (water soluble) part COONa or COOK. The cleansing action of the soap depends upon the solubility of the long alkyl are in grease or oil droplets and that of COONa or COOK part in water. The dirt is held on the surface of the cloth by grease or oil droplets. Whenever soap is applied on a dirty wet cloth, the non-polar alkyl group dissolves in grease (non-polar) while the polar COONa group dissolves in water (polar). In this way an emulsion is formed between grease and water which appears as foam. The dirt along with the emulsion is washed away when the cloth is treated with excess of water. Thus, the washing capacity of soap depends upon its foaming capacity, i.e. the extent to which it produces foam with water. The foaming capacity also depends upon the quality of water used. If soft water is used, soaps easily produce lot of lather. On the other hand, if hard water is used, even good quality soaps will not produce lather. The reason being that hard water contains magnesium and calcium ions which form insoluble magnesium and calcium salts of carboxylic acids which in turn, precipitate out in the form of a scum. 2C17H35COONa + Ca2+ → (Water Soluble) 2C17H35COONa (Water Soluble) (C17H35COO)2 Ca ↓ + 2Na+ + 2Na+ (ppt.) + Mg2+ → (C17H35COO)2 Mg ↓ (ppt.) However, if hard water is first treated with Na2CO3, magnesium and calcium ions present in it and precipitate as their insoluble carbonates. The filtrate can be used for washing purposes since it is now rendered soft. In contrast, detergents can be used for washing purposes even in hard water. The reasons being that detergents are sodium or potassium salts of aliphatic or aromatic sulphonic acids and even their calcium and magnesium salts are soluble in water and thus do not form scum but form foam when treated with hard water. EXPERIMENT:OBJECTIVE: To compare the foaming capacity of different soaps. APPARATUS: Five 100ml conical flasks, five 20ml test tubes, 100ml measuring cylinder, test tube stand, weight box and stop watch. CHEMICALS REQUIRED: Five different samples of soap, distilled water. THEORY: The foaming capacity of soap depends upon the nature of the soap and its concentration. This may be compared by shaking equal volumes of the solutions of the different samples of soaps having the same concentration with the same force and for same period of time. The solutions are then allowed to stand when the foam produced during shaking disappears gradually. The time taken for the foam to disappear in each sample is determined.The longer the time taken for the disappearance of foam in the given sample of soap, greater is its foaming capacity or cleansing capacity. PREOCEDURE: 1. Take five 100ml conical flasks and number them as 1, 2, 3, 4 and 5. Put 50ml of distilled water in each of conical flasks and add 5gm of soap shavings or granules of different soap samples to each flask. 2. Warm the contents of each flask to get a clear solution. 3. Take five 20ml test tubes and add 10ml of distilled water to each one of them and label them as 1, 2, 3, 4 and 5. Now add 1ml of soap solution from each conical flask to the corresponding test tube. 4. Close the mouth of the test tube number 1 with your thumb and shake its contents vigorously for one minute. Place test tube in the test tube stand and start the stop watch immediately. Note the time taken for disappearance of the foam produced. 5. Repeat the same procedure for test tubes 2, 3, 4 and 5 shaking each time with the same force and for the same time (one minute). Note the time taken for disappearance of foam in each case and record the observations in a tabular form. OBSERVATIONS: Amount of each soap sample taken = of distilled water added to each soap sample 5.0gm = 50.0ml Test Tube Number Name of the Soap Sample Volume of Soap Solution Added Volume of Water Added 1. 2. 3. 4. 5. Dove Lifebuoy Dettol Lux Liril Medimix 1.0ml 1.0ml 1.0ml 1.0ml 1.0ml 1.0ml 10.0ml 10.0ml 10.0ml 10.0ml 10.0ml 10.0ml 6. Volume Time of disappearance of foam RESULT: The foaming capacity and hence the cleansing capacity of different samples of soaps is in the order: Lifebuoy > Dettol > Liril > Lux > Medimix > Dove PRECAUTION: Each test tube containing the soap solution must be shaken with the same force and for the same period of time. BIBLIOGRAPHY ⮚ TEXT BOOK OF CLASS 12th CHEMISTRY ⮚ http://www.google.co.in ⮚ http://www.wikipedia.org ⮚ http://www.youtube.com ⮚ http://www.slideshare.net ⮚ Help from Subject Teacher and Lab Attender.
