Chemistry In Everyday Life Book Back Questions 6th Science Lesson 17

6th Science Lesson 17

17] Chemistry In Everyday Life

Book Back Questions with Answer and Do You Know Box Content

Do You Know?

When we cut onion, we get tears in the eyes with irritation, because of the presence of a chemical, propanethial s-oxide in onion. This is easily volatile. When we cut onion some of the cells are damaged and this chemical comes out. It becomes vapour and reach our eyes result in irritation and tears in eyes. When we crush the onion, more cells will be damaged and more chemicals come out.

Earthworms take organic wastes as food and produce compost castings. So earthworms are known as Farmers’ friends because of the multitude of services they provide to improve soil health and consequently plant health.

In 1824, Joseph Aspdin invented Portland cement by burning finely ground chalk and clay in a kiln. It was named “Portland” cement because it resembled the high-quality building stones found in Portland, England.

Choose the best answers:

1. Soaps were originally made from _______________.

(a) Proteins

(b) Animal fats and vegetable oils

(c) Chemicals extracted from the soil

(d) Foam booster

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

3. Gypsum is added to the cement for ______________

(a) Fast setting

(b) Delayed setting

(c) Hardening

(d) Making paste

4. Phenol is ________________

(a) Carbolic acid

(b) Acetic acid

(c) Benzoic acid

(d) Hydrochloric acid

5. Natural adhesives are made from ______________

(a) Protein

(b) Fat

(c) Starch

(d) Vitamins

Fill in the blanks:

1. ______________ gas causes tears in our eyes while cutting onions.

2. Water, coconut oil and ______________ are necessary for soap preparation.

3. _______________ is called as farmer’s best friend.

4. _____________ fertilizer is eco-friendly.

5. ______________ is an example for natural adhesive.

State true or false. If false, correct the statement:

1. Concentrated phenol is used as a disinfectant.

2. Gypsum is largely used in medical industries.

3. Plaster of Paris is obtained from heating gypsum.

4. Adhesives are the substances used to separate the components.

5. NPK is the primary nutrients for plants.

Match the following:

1. Soap – C₆H₅OH

2. Cement – CaSO₄.2H₂O

3. Fertilizers – NaOH

4. Gypsum – RCC

5. Phenol – NPK

Complete the analogy:

1. Urea: Inorganic fertilizer ::Vermi compost: ___________

2. _________________: Natural adhesives ::Cello tape: Artificial adhesives.

Answers:

Choose the best answers:

1. Animal fats and vegetable oils 2. Sodium hydroxide 3. Delayed setting 4. Carbolic acid 5. Starch

Fill in the blanks:

1. Propanethial-s-oxide 2. Animal fat 3. Earthworms 4. Organic 5. Starch dissolved in water

Say True or False:

1. False

Correct Statement: Low concentrated phenol is used as a disinfectant.

2. False

Correct Statement: Gypsum is largely used in cement preparations.

3. True

4. False

Correct Statement: Adhesives are the substances used to join the components.

5. True

Match the following:

1. NaOH 2.RCC 3.NPK 4. CaSO₄.2H₂O 5. C₆H₅OH

Complete the Analogy:

1. Organic fertilizers 2. Starch dissolved in water