Advertisements
Advertisements
Question
Why do soaps not work effectively in hard water?
Solution
Calcium and magnesium ions can be found in hard water. In hard water, these ions displace sodium or potassium from the salts that make up soaps, forming insoluble calcium or magnesium salts of fatty acids. As scum, these insoluble salts separate. This explains why soap does not dissolve in hard water.
APPEARS IN
RELATED QUESTIONS
Hard water is not available for an experiment. Some salts are given below :
(I) Sodium chloride
(II) Sodium sulphate
(III) Calcium chloride
(IV) Calcium sulphate
(V) Potassium chloride
(VI) Magnesium sulphate
Select from the following group of these salts, each member of which may be dissolved in water to make it hard.
(A) I, II, V
(B) I, III, V
(C) III, IV, VI
(D) II, IV, VI
Would you be able to check if water is hard by using a detergent?
Why does micelle formation take place when soap is added to water? Will a micelle be formed in other solvents such as ethanol also?
What change will you observe if you test soap with litmus paper (red and blue)?
How is soap made? Write a word equation involved in soap making.
What is saponification? Write the chemical equation of the reaction involved in this process. Name all the substances which take part in this process and also those which are formed.
Which one of the following sets of materials can be used to prepare soap?
(A) Neem oil and calcium hydroxide
(B) Castor oil and sodium hydroxide
(C) Mineral oil and sodium hydroxide
(D) Neem oil and magnesium hydroxide
How will you check with the help of soap powder whether water is hard?
Water, coconut oil, and _______ are necessary for soap preparation.
Arrange the following statements in correct sequence
- Pour that solution into an empty matchbox, soap can be obtained after drying.
- Take the necessary quantity of water in a jar.
- Then add coconut oil drop by drop and stir it well.
- Add concentrated sodium hydroxide in the jar and allow it to cool.
- Try this soap to wash your hand kerchief.
- Cover your work area with old newspaper.
