... soap...

...what is soap....

1)soap is a salt that is formed from the reaction between an alkali and a fatty alkali. 

 2)Soap is a:-

             

         a)sodium salt fatty acid if the alkali used is

sodium hydroxide.

       b)potassium salt fatty acid if the alkali used is  
potassium hydroxide.

alkali + fatty acid ----> sodium/potassium salt fatty acid + 

water(soap)

3)The general formula of soap is RCOONa  

orRCOOK.R is a long-chained alkly group

  4)Example of soap include:

       a)sodium palmitate,

     
       b)sodium stearate,

       
       c)sodium laurate,


       d)sodium oleate,

...soap preparation process...

1) soap can be preparde by heating fat or oil together with 

alkali through the saponification process


2)the saponification process is a hydrolysis process of

ester( oil or fat) by alkali

      
 3)the vegitable oil that is usually used to manufacture 

soap is palm oil,coconut oil and olive oil

         
     4)the manufacturing of soap can be divided into two 

                 stages,that is                

          stage1

            a)    the two parts of the oil or fat (ester) molecule 

                  are separated by heating the oil with                         

                 alkaline solution through the hydrolysis process.

            

          b)   in this process, the oil or fat(ester) molecule is 

                broken up into fatty acid and glycerol by water in 
               the presence of alkali which acts as a catalyst

          

         stage 2

                the fatty acid that is released in stage 1 reacts 

with alkali to form sodium salt fatty acid which is soap .

  

             

fatty acid + sodium hydroxide ---> sodium salt fatty acid + water

                                     (alkali)                           (soap)

        5)generally, the soap manufacturing reaction is 

            represented by a chemical equation in words. The reaction is as follows

vegetable oil + sodium hydroxide ---> sodium salt  fatty acid + glycerol  

                  (ester)              (alkali)                            (soap)                 (alcohol)

         6)the soap that is produced can be precipitated out 

from the mixture by adding table salt that is sodium 

chloride.

         7)sodium chloride is added to reduce the solubility of 

      soap in water and cause the soap to be seperated from 

the solution 

        
 8)the soap that is produced is filtered, purified and added 

with additives such as biological enzymes, wihtening 

agents, antiseptics, perfumes and colouring.

          
  9)there are two types of soap : 

           a) solid soap - made from sodium hydroxide and 

                                   saturated carboxylic acid that is          found in the animal fat 

                                 -used for bathing and washing clothes

           

             b)liquid soap - made from potassium hydroxide 

                                    and unsaturated carboxylic acid        that is found in plant oil    

                 

                                   -used as liquid soap ang shaving         cream (more expnsive).