Soaps, Detergents And Water

Question 1

What materials are used for saponification?

Answer 1

-Vegetable oil or animal fat
-Concentrated sodium/potassium hydroxide
-Concentrated sodium chloride solution

Question 2

What is Involved in the process of saponification?

Answer 2

1. Vegetable oil or animal fat is boiled with concentrated sodium hydroxide until frothing stops. Soap is formed in solution.
2. Concentrated sodium chloride solution is added so as to precipitate out soap by lowering it’s solubility in the mixture(salting process). The precipitated soap floats on top of the liquid mixture
3. The precipitated soap is filtered off.

Question 3

What is the cleansing action of soap?

Answer 3

Soap is used on stained fabric in water, the inorganic part of soap dissolves the stain. Agitation causes emulsification of stains forming tiny droplets (micelles) which are carried away by water.

Question 4

What happens when soap is used in hard water?

Answer 4

It forms scum 

Question 5

What is scum?

Answer 5

Scum is an insoluble curd(precipitate) of Calcium or magnesium stearate

Question 6

Give 3 advantages of soaps Over detergent?

Answer 6

• Soap is more friendly to the skin unlike detergent.
• Soap is cheaper than detergent.
  -Soup is environmentally friendly since it is biodegradable.

Question 7

Give three advantages of detergents over soap?

Answer 7

• Detergent and more soluble In water than soap.
• Detergent do not form scum with hard water unlike soap.
• Detergents are more effective on stains compared to soaps.