Samacheer Kalvi 6th Science Term 3 Solutions Chapter 3 Pdf

Samacheer Kalvi 6th Science Term 3 Solutions Chapter 3 Pdf

Tamilnadu Board Samacheer Kalvi 6th Science Term 3 Solutions Chapter 3: Tamilnadu State Board Solution Class 6 Science Term 3 Chapter 3 – Chemistry in Everyday life.

Samacheer Kalvi 6th Science Term 3 Solutions Chapter 3: Overview

Board

Samacheer Kalvi
Class

6

Subject

Science
Chapter

3

Chapter Name

Chemistry in Everyday life

Samacheer Kalvi 6th Science Term 3 Solutions Chapter 3 Pdf

I.) Choose the correct answer.

1.) Soaps were originally made from ___________ .

a.) Proteins

b.) Animal fats and vegetable oils

c.) Chemicals extracted from the soil

d.) Foambooster

Answer:Animal fats and vegetable oil

Solution: Soaps were originally made from animal fats and vegetable oil because they have high cleansing properties and are gentle to our skin.

 

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.) Sodiumchloride

Answer: Sodium chloride

Solution: Because sodium chloride (NaOH) is insoluble in water, it is widely used in saponification of a fat or oil or soap.

 

3.) Gypsum is added to the cement for ______________________.

a.) Fast setting

b.) delayed setting

c.) Hardening

d.) making paste

Answer: Delayed setting

Solution: Gypsum is added to the cement during the final grinding process. It is used to control the setting of the cement.

 

4.) Phenol is ________________.

a.) Carbolic acid

b.) acetic acid

c.) Benzoic acid

d.) hydrochloric acid

Answer:Carbolic acid

Solution: The molecules of Phenol are highly acidic so they are often referred to as Carbolic acid.

 

5.) Natural adhesives are made from ___________.

a.) Protein

b.) fat

c.) Starch

d.) vitamins

Answer:Starch

Solution: Organic sources such as vegetable starch, natural resins etc are used to make natural adhesives. These are called bio-adhesives.

 

II.) Fill in the Blanks

1.)___Propanethial_s-oxide____ gas causes tears in Our eyes while cutting onions.

 

2.) Water, coconut oil and ___animal fat_______ are Necessary for soap preparation.

 

3.) __Earthworm______ is called as farmer’s Best friend.

 

4.) __organic______ fertilizer is ecofriendly.

 

5.) ___Starch dissolved in water______ is an example for Natural adhesive.

 

III.) True or False. If False, give the Correct statement

 

1.) Concentrated phenol is used as a Disinfectant.

Answer: False, Low Concentrated phenol is used as a Disinfectant.

 

2.) Gypsum is largely used in medical Industries.

Answer: False, Gypsum is largely used in cement Industries.

 

3.) Plaster of Paris is obtained from heating Gypsum.

Answer:True

 

4.) Adhesives are the substances used to Separate the components.

Answer:False, Adhesives are the Substances used to combine the components.

 

5.) NPK are the primary nutrients for Plants.

Answer: True

 

IV.) Match the following

Answer:

Soap NaOH
Cement RCC
Fertilizer NPK
Gypsum CaSO4.2H2O
Phenol C6H5OH

 

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:

6.) Cover your work area with old Newspaper.

2.) Take necessary quantity of water in a Jar.

4.) Add concentrated sodium hydroxide in The jar and allow it to cool.

3.) Then add coconut oil drop by drop and Stir it well.

1.) Pour that solution into an empty match Box, soap can be obtained after drying.

5.) Try this soap to wash your hand Kerchief.

 

VI.) Analogy

1.) Urea : Inorganic fertilizer:Vermi compost: ____________.

Answer:Organic fertilizer

 

2.)_____________: Natural adhesives: Cello tape: Artificial adhesives.

Answer: Starch dissolved in water

 

VII.) Give very short answer

 

1.) What are the three main constituents Of soap?

Answer: Lye, coconut oil and water are the three main constituents of soap.

 

2.) What are the two different types of Molecules found in the soap?

Answer:Loving water molecules and hating water molecules are two different types of molecules found in the soap.

 

3.) Give an example for inorganic fertilizer.

Answer: Urea is an example of inorganic fertilizer.

 

4.) Mention any three physical properties Of phenol.

Answer: Properties of phenol are :

  • White crystalline powder
  • Weak acid
  • High volatile

 

5.) Explain the uses of plaster of paris.

Answer: Plaster of Paris is used in statues and toys, in surgery for setting fractured bones, in making blackboard chalks etc.

 

6.) What are the ingredients of the Cement?

Answer:Limestone, gypsum and clay are the ingredients of cement.

 

7.) Why gypsum is used in cement Production?

Answer: Gypsum is used in cement Production because it helps in controlling the setting of the cement.

 

VIII.) Give short answer

1.) Why earthworm is called as farmer’s Friend?

Answer:Earthworms produce compost castings and also improves the quality and health of the soil. Therefore they are known S farmer’s friend.

 

2.) Explain the process of manufacturing Cement.

Answer:Minerals that can be naturally obtained such as clay, limestone, gypsum and are all crushed using a milling process to prepare cement.

 

3.) What are uses of Gypsum?

Answer:Gypsum is used for making plaster of Paris. Cement is also prepared using Gypsum. It also used as a fertilizer.

 

IX.) Answer in detail

1.) How are detergents manufactured?

Answer:Materials used in the preparation of detergents are: acid slurry, soda ash or sodium carbonate, trisodium phosphate, sodium tripolyphosphate, cellulose or Carboxy methyl chloride, colour perfume, brightner and glauber’s salt.

Preparation process:

The first step is the neutralization of acid slurry. Then it is mixed with soda ash or sodium carbonate and for complete reaction to take place this mixture is kept for an hour. Other materials like trisodium phosphate, sodium tripolyphosphate, cellulose or Carboxy methyl chloride, colour perfume, brightner and glauber’s salt are all with continuous mixing add to the mixture of neutralized acid slurry. This mixture is then kept for drying and as a result detergent is formed.

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.

Answer:

  • Construct a cement tub with a height of 2’A feet and a breadth of 3 feet. Now upto a height of 5cm fill the cement tub with bio wastes. Next Add some earthworms to it. Above the bio wastes add sawdust, coir wastes and husk. Now form a layer of sand upto 3cm. Adding garden waste and then watering the layers to moisten it . After 10-15 days , the vermi-compost manure is ready.

Benefits:

  1. Vermi-composting prevents soil corrosion and improves the soil texture and structure.
  2. It neutralizes soil protection.
  3. It consists of valuable hormones like auxins.
  4. It is rich in nutrients.
Updated: June 15, 2022 — 1:50 am

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