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Class VI S T3 Chemistry in Everyday Life Textbook Solutions
Unit 3
CHEMISTRY IN EVERYDAY LIFE
Evaluation
I. Choose the appropriate answer
1. Soaps were originally made from ___________ .
a. proteins
b. animal fats and vegetable oils
c. chemicals extracted from the soil
d. foam booster
Ans: b. animal fats and vegetable oils
2. The saponification of a fat or oil is done using _______________ solution for hot process.
a. Ammonium hydroxide
b. Sodium hydroxide
c. Hydrochloric acid
d. Sodium chloride
Ans: b. Sodium hydroxide
3. Gypsum is added to the cement for ______________________.
a. fast setting
b. delayed setting
c. hardening
d. making paste
Ans: b. delayed setting
4. Phenol is ________________.
a. carbolic acid
b. acetic acid
c. benzoic acid
d. hydrochloric acid
Ans: a. carbolic acid
5. Natural adhesives are made from ___________.
a. Protein
b. fat
c. starch
d. Vitamins
Ans: c. starch
II. Fill in the Blanks
1. ______________ gas causes tears in our eyes while cutting onions.
Ans: Propanethial S-Oxide
2. Water, coconut oil and __________ are necessary for soap preparation.
Ans: animal fat
3. ____________ is called as farmer’s best friend.
Ans: Earthworm
4. ___________ fertilizer is ecofriendly.
Ans: Organic
5. _____________ is an example for natural adhesive.
Ans: Strarch
III. True or False. If False, give the correct statement
1. Concentrated phenol is used as a disinfectant.
Ans: False. Diluted phenol is used as a disinfectant
2. Gypsum is largely used in medical industries.
Ans: Flase. Gypsum is largely used in cement industries.
3. Plaster of Paris is obtained from heating gypsum.
Ans: True
4. Adhesives are the substances used to separate the components.
Ans: False.Adhesives are the substances used to join the components.
5. NPK are the primary nutrients for plants.
Ans: True
IV. Match the following
1. Soap - NaOH
2. Cement - RCC
3. Fertilizers - NPK
4. Gypsum - CaSO4.2H2O
5. Phenol - C6H5 OH
V. Arrange the following statements in correct sequence
1. Pour that solution into an empty match box, soap can be obtained after drying.
2. Take necessary quantity of water in a jar.
3. Then add coconut oil drop by drop and stir it well.
4. Add concentrated sodium hydroxide in the jar and allow it to cool.
5. Try this soap to wash your hand kerchief.
6. Cover your work area with old newspaper.
Answer:
Cover your work area with old newspaper.
Take necessary quantity of water in a jar.
Add concentrated sodium hydroxide in the jar and allow it to cool.
Then add coconut oil drop by drop and stir it well.
Pour that solution into an empty match box, soap can be obtained after drying.
Try this soap to wash your hand kerchief.
VI. Analogy
1. Urea : Inorganic fertilizer: Vermi compost: ____________.
Ans: Organic fertilizer
2. _____________: Natural adhesives: Cello tape: Artificial adhesives.
Ans: Starch
VII. Give very short answer
1. What are the three main constituents of soap?
The three main constituents of soap are
Sodium hydroxide
Coconut Oil
Water
2. What are the two different types of molecules found in the soap?
The two different types of molecules found in the soap are
Water loving molecule
Water hating molecule
3. Give an example for inorganic fertilizer.
Examples for inorganic fertilizer are
Urea
Ammonium sulphate
Super phosphate
4. Mention any three physical properties of phenol.
Phenol is a weak acid
Volatile
White crystalline powder
5. Explain the uses of plaster of paris.
Plaster of paris is
Used in surgery for setting fractured bones
Used for making casts for statues and toys.
6. What are the ingredients of the cement?
Limestone
Clay
Gypsum
7. Why gypsum is used in cement production?
Gypsum is used to control the ‘Setting of cement’.
VIII. Give short answer
1. Why earthworm is called as farmer’s friend?
Earthworms take organic wastes as food and produce compost castings and the multitude of services they provide to improve soil health and consequently plant health.Hence, earthworms are called as Farmers' friends.
2. Explain the process of manufacturing cement.
The cement is manufactured by crushing of naturally occurring minerals such as lime, clay and gypsum through milling process.
3. What are uses of Gypsum?
Gypsum is
Used as fertilizers.
Used in the process of making cement.
Used in the process of making Plaster of Paris
IX. Answer in detail
1. How are detergents manufactured?
Detergents are chemicals that are used to break down and remove dirt, grease, and stains.
Detergents work by binding to the dirt and grease molecules and breaking them down into smaller pieces. This makes them easier to wash away.
Detergents are manufactured using a synthetic surfactant in place of the metal fatty acid salts that are used in soaps.
Chemical Processes
Powder detergents are manufactured using various processes, such as spray drying, agglomeration, dry mixing or a combination of these.
Anionic Surfactants
The hydrocarbons that are extracted from the fats and oils or petroleum undergo a chemical reaction and produce newer acids that are similar to the fatty acids. An alkali is then added to the acid produced and gives anionic surfactant molecules.
Non-ionic Surfactants
The hydrocarbons are converted to alcohol and then reacted with ethylene oxide. The surfactants produced are then reacted further with the acids containing sulfur and form another kind of anionic surfactant.
X. Questions based on Higher Order Thinking Skills
1. Ravi is a farmer; he rears many cattle in his farm. His field has many bio wastes. Advise Ravi how to change this bio waste to compost by using vermi -composting techniques. Explain the benefits of vermi castings.
Benefits of Vermicast:
The worm digests the organic materials it consumes, it refines them. Nutrients, including minerals and trace elements, are reduced to their most usable form.
The castings have a neutral pH of 7.0.
Vermicast makes soil more absorbent, making moisture more consistently available to plants and preventing soil from completely drying out.
Worms introduce uncountable numbers of beneficial microbes, bacteria, and fungi into the finished product.
Vermicast also improves soil structure by simultaneously boosting aeration, enhancing drainage, and promoting water retention.
