Class 6 - Science - CH4 - Sorting Materials into Groups

NCERT Chapter Answers and  other Q & Answers

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Q1: Name five objects which can be made from wood.

Answer:

1. Chair
2. Table
3. Plough, 
4. Bullock cart and its wheels
5. Door

Q2: Select those objects from the following which shine:

      Glass bowl, plastic toy, steel spoon, cotton shirt

Answer: Objects which shine are: Glass bowl and steel spoon.

Q3: Match the objects given below with the materials from which they could be made. Remember, an object could be made from more than one material and a given material could be used for making many objects.

Objects	Materials
Book	Glass
Tumbler	Wood
Chair	Paper
Toy	Leather
Shoes	Plastics

Answer:

Objects	Materials
Book	Paper
Tumbler	Glass
Chair	Wood
Toy	Plastics
Shoes	Leather

Q4: State whether the statements given below are True or False. 

(i) Stone is transparent, while glass is opaque. 

(ii) A notebook has lustre while eraser does not. 

(iii) Chalk dissolves in water. 

(iv) A piece of wood floats on water. 

(v) Sugar does not dissolve in water.
(vi) Oil mixes with water.
(vii) Sand settles down in water.
(viii) Vinegar dissolves in water.

Answer: 

(i) Stone is transparent, while glass is opaque.  ✗ (False)

(ii) A notebook has lustre while eraser does not.  ✗ (False)

(iii) Chalk dissolves in water. ✗ (False)

(iv) A piece of wood floats on water. ✓ (True)

(v) Sugar does not dissolve in water. ✗ (False)
(vi) Oil mixes with water. ✗ (False)
(vii) Sand settles down in water. ✓ (True)
(viii) Vinegar dissolves in water. ✓ (True)

Q5: Given below are the names of some objects and materials:
  Water, basket ball, orange, sugar, globe, apple and earthen pitcher
 

Group them as:
(a) Round shaped and other shapes
(b) Eatables and non eatables

Answer:

(a) Round shaped and other shapes:

Round Shaped	Other Shapes
Basket Ball Orange Globe Earthen Pitcher	Water Apple Sugar

(b) Eatables and non eatables

Eatables	Non Eatables
Water, Orange, Sugar, Apple	Basket Ball Globe Earthen Pitcher

Q6: List all items known to you that float on water. Check and see if they will float on an oil or kerosene.

Answer: Paper strip, Balloon, Hair, plastic bottle, Wood, Boat etc. will float on water. A few of these like hair, balloon can float on kerosene or oil. 

Generally, substances have less density than oil and water can float. For example, few types of wood have densities higher than oil but less than water, so it floats on water but not on kerosene.

Q7: Find the odd one out from the following:

a) Chair, Bed, Table, Baby, Cupboard

b) Rose, Jasmine, Boat, Marigold, Lotus

c) Aluminium, Iron, Copper, Silver, Sand

d) Sugar, Salt, Sand, Copper sulphate

Answer:

(a) Baby (rest are made up of wood).

(b) Boat (others are flowers)

(c) Sand (others are metals).

(d) Sand (others are soluble in water).

Q8: How can materials be grouped together? In what ways do we classify materials?

Answer: Different materials have different properties. Depending on the similar properties among different materials, these can be grouped together.

Different types of materials can be grouped based on the following properties they posses:

• Appearance, 
• Solubility, 
• Transparency, 
• Conductivity
• Combustible - Easily burn or not.
• Attracts towards magnet 

Q9: Why do we classify  materials in different groups?

Answer: Different materials are grouped for the following reasons:

1. For our convenience. For example we can easily locate and identify them.
2. It helps us study their properties and identify common patterns among them.

Q10: What do you call a substance through which things are partially visible? 

Answer: Translucent object.

Q11: Name the materials that have fixed volume but not fixed shape.

Answer: Liquids like water, oil etc.

Q12: Roma has a bag full of apples. A few of these apples are rotten. How does Roma separate rotten apples from good ones?

Answer: By looking and smelling them, Roma can identify rotten apples. Rotten ones look mushy and pulpy and smell bad.

Q13: Is Oiled paper transparent, translucent or opaque?

Answer: Translucent.

Q14:  Give examples of transparent materials.

Answer: Glass, water, air and some plastics.

Q15: Why do shopkeepers prefer to keep biscuits, sweets and other eatables in transparent containers?

Answer: Because buyers can easily see these items.

Q16: Which of the following objects are soluble in water?

Chalk powder, sugar, clay, table salt

Answer: Sugar and salt are soluble in water, while chalk powder and clay are not soluble in water.