Advertisements
Advertisements
प्रश्न
Give a scientific explanation.
Soap forms a precipitate in hard water.
Advertisements
उत्तर
When soap is mixed with hard water calcium and magnesium salts of fatty acids are formed. These being water insoluble they form a precipitate and that is why lather is not formed.
APPEARS IN
संबंधित प्रश्न
What change will you observe if you test soap with litmus paper (red and blue)?
Why is common salt (sodium chloride) added during the preparation of soap?
Which of the two is better for washing clothes when the water is hard: soap or detergent? Give reason for your answer.
Describe the structure of a soap molecule with the help of a diagram.
The chemical which is not required for the preparation of soap in the laboratory is:
(a) vegetable oil
(b) baking soda
(c) caustic soda
(d) common salt
The chemical mostly used in the preparation of most of the soaps we use is
(a) Sodium chloride
(b) Potassium hydroxide
(c) Sodium hydroxide
(a) Potassium chloride
A student is testing water to know which is best for cleansing purposes with soaps. He would find that the cleansing action of soaps is best when he uses water obtained from
(a) rain
(b) tap
(c) hand pump
(d) pond
What is the difference between the chemical composition of soaps and detergents? State in brief the action of soaps in removing an oily spot from a shirt. Why are sops not considered suitable for washing where water is hard?
Differentiate between:
Detergents and Soaps.
What is meant by ‘surface activity’?
Name three chemicals responsible for the surface activity of various detergents.
What are the differences between Bath soap and soap for washing clothes?
Soaps were originally made from ______.
The saponification of a fat or oil is done using _____ solution for hot process.
The alkaline hydrolysis of fatty acids is termed as ______
______ molecules go and join with dirt and oil in the cloth.
