What is soap ? How would you make soap in the laboratory ? State one advantage and one disadvantage of soap over synthetic detergents.
What is soap ? How would you make soap in the laboratory ? State one advantage and one disadvantage of soap over synthetic detergents.
Soaps are sodium or potassium salts of long chain fatty acids. Soap can be prepared in laboratory by heating the naturally occuring oil or fat with sodium hydroxide. On heating, sodium salt of the fatty acid soap is formed along with glycerol. This process is known as saponification.
Oil or fat + NaOH → Soap + Glycerol
The soap is precipitated by adding common salt to the above solution. Soap being lighter, floats on water and is filtered. It is cooled and then cut into pieces.
Soaps have the advantage over detergents that they are biodegradable and do not cause water pollution. The disadvantage of soaps over detergents is that, they cannot be used in hard water.
Soaps are sodium or potassium salts of long chain fatty acids. Soap can be prepared in laboratory by heating the naturally occuring oil or fat with sodium hydroxide. On heating, sodium salt of the fatty acid soap is formed along with glycerol. This process is known as saponification.
Oil or fat + NaOH → Soap + Glycerol
The soap is precipitated by adding common salt to the above solution. Soap being lighter, floats on water and is filtered. It is cooled and then cut into pieces.
Soaps have the advantage over detergents that they are biodegradable and do not cause water pollution. The disadvantage of soaps over detergents is that, they cannot be used in hard water.
