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INDEX  

 AIM

 APPARATUS AND CHEMICALS USED

 THEORY

 PROCEDURE

 EXPERIMENTAL SETUP

 OBSERVATIONS

 TEST ANALYSIS

 INFERENCE

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 AIM a) To analyse which is a better cleansing agent detergent or soap.b) To analyse which is a better moisturizing agent soap or detergent.    

APPARATUS AND CHEMICALS USED             

Test tubes, test tube stand, distilled water, dil. HCL, burner,

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detergent powder, and dove beauty soap.

THEORY Cleansing action of soap and detergents: ·       Soaps and detergents remove dirt and grease from skin and clothes. But all soaps are not equally effective in their cleansing action. Soaps are the Na and K salts of higher fatty acids such as Palmitic acid, Stearic acid and Oleic acid. ·       The cleansing action of soaps or detergents depends on the solubility of the long alkyl chain in grease and that of –COONa or the –COOK part in water. ·       Whenever soap or detergent is applied on a dirty wet cloth, the non-polar alkyl group dissolves in grease while the polar –COONa part dissolves in

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water. In this manner, an emulsion is formed between grease and water which appears as foam. ·       The washing ability of soap or detergent depends on foaming capacity, as well as the water used in cleaning. ·       the salts of Ca and Mg disrupt the micelle formation. The presence of such salts makes the water hard. These salts thus make the soap inefficient in its cleaning action. ·       This problem is solved by detergents which have high foaming capacity and thus have very efficient cleaning action. ·       Thus, higher the foaming capacity, better the cleansing action.      

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      Moisturizing action of soap or detergents: ·       Soap contains alkali matter, which affects our skin and even skin may crack. ·       To maintain the oily and moisture balance on our skin, fatty acid is required in soap. In general, the fatty matter in soap is approximately 70% to 80%. Fatty matter below 70% make our skin dry and rough whereas higher percentage of fatty matter i.e., above 80% make the soap sticky and oily and therefore washing becomes very difficult using soap. Detergents in turn contain very less amount of fatty acids and therefore are more suitable for washing clothes than soap. 

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PROCEDURE ·       About 0.3g of each soap and detergent sample was taken in a clean test tube.·       Water was added to both the test tubes and a solution was formed.·       Test tube containing detergent should be labelled as Test Tube-A and soap solution as Test Tube-B.·       Both the test tubes were shook for 1 minute and therefore foam was formed.·       The time for which the foam was present in the test tube was noted down.

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·       Now dil. HCL was added to both the test tubes and heated.·       The amount of oily matter formed on the uppermost layer was observed.       

OBSERVATIONS 

·       Time taken by foam in Test Tube-B to disappear = 5 minutes.·       Time taken by foam in Test Tube-A to disappear = 2 minutes.·       Amount of oily material formed was greater in Test Tube-B than in Test Tube-A.  

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TEST ANALYSIS ·       The experiment performed proved that since the foam produced by detergent solution existed for a longer period of time and also the fatty material present in it is in lesser quantity, detergents are suitable for cleaning and washing purposes and not for usage on skin. ·       The foam produced due to soap solution existed for a lesser period of time and contained greater amount of fatty material and therefore is

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suitable for usage on skin and for washing purposes.   

  INFERENCE Difference between soaps and detergents Soaps Detergents 1) Soap are sodium salt of   long chain carboxylic acids.  

2) Soaps are not suitable for washing purpose when water is hard. 

1) Synthetic detergents are sodium salts of long chain benzene sulphonic acid.

 2) Synthetic detergent can be used for

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3) Soaps have relatively weak cleansing action.

washing even when water is hard. 

3)Synthetic detergent have a strong cleansing agents

     

Bibliography Parts of this project have been referred from the previous year’s projects and have been included in this investigatory project after editing.The references of the sources are as follows:Books:

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Together with Lab Manual Chemistry-XIIComprehension Chemistry-XII