Karnataka Board Class 8 Science Chapter 16 States of Matter
KSEEB Class 8 Science Chapter 16 Textual Questions & Answers
I. Four alternatives are given to each of the following incomplete statements question. Choose the right answer.
Question 1.
Which one of the following does not hold good for liquid
(a) They have definite volume
(b) They are slightly compressible than solids
(c) Molecules are free to move within the substance
(d) They have definite shape and size.
Answer:
(d) They have definite shape and size.
Question 2.
Which of the following is not a pure substance
a) Common salt
b) sugar
c) Rain water
d) Iron
Answer:
c) Rain water
Question 3.
The component which is not present in air is
a) Nitrogen
b) Oxygen
c) Carbon dioxide
d) Chlorine
Answer:
d) Chlorine
Question 4.
Butter is an example for
a) Liquid in solid
b) Solid in liquid
c) Liquid in liquid
d) Solid in solid
Answer:
b) Solid in liquid
II. Answer the following.
Question 1.
Write any four differences between solid, liquid and gases.
Answer:
Solids | Liquids | Gases |
1) Particles are closely packed | Particles are free to move within substances | Particles are not fixed to a position and are more free than liquids. |
2) They have definite shape | They assume the shape of container | do not have definite shape |
3) They posses definite volume | They have definite volume | do not have definite volume |
4) Very low compressibility | Slightly more compressible than solids | Compressibility is very high. |
Question 2.
Differentiate between a homogeneous and heterogeneous solution with an example.
Answer:
Homogeneous solution | Heterogeneous Solution |
A mixture in which different constituents mix uniformly | A mixture in which different constituents do not mix uniformly |
The components of the mixture are not visible | The components of the mixture are visible |
Eg:- Alloys, Air crude oil | Eg:- Mixture of water and oil, Mixture of salt and copper sulfate |
Question 3.
Give an example to each of the following
- Suspension
- Colloidal solution
Answer:
- Suspension – Sawdust added to water
- Colloidal solution – Milk
Question 4.
Define
- Tyndall Effect
- Brownian movement
Answer:
- Tyndall Effect
- Scattering of a beam of light by the colloids is called the Tyndall effect.
- Tyndall effect can be observed when sunlight passes through canopy of a dense forest.
- Brownian movement
- The random motion (zig-zag motion) of small colloidal particles suspended in a liquid of gas medium is called a Brownian movement.
Question 5.
Give any two examples for solvents other than water
Answer:
Chloroform, Turpentine oil, Petrol, Carbon tetrachloride.
III. Give a scientific reasons for the following.
Question 1.
Gases do not have definite shape and volume
Answer:
In gases the particles are not fixed to a position and are freer to move in the space available to them. Hence they do not have definite shape and volume.
Question 2.
Ornamental gold is an example for a homogeneous mixture.
Answer:
Ornamental gold is an alloy of gold and copper in which the components of the mixture is uniform and not visible with a naked eye.
Question 3.
Mixture of sand and iron filings is a heterogeneous mixture.
Answer:
In sand and Iron filings the components of mixture do not mix uniformly and they are visible to the naked eye itself.
Question 4.
Water is called a Universal solvent.
Answer:
Water can dissolve a large number of salts in it. Hence it is known as the universal solvent.
Question 5.
When a beam of light is passed through a suspension, its path is visible.
Answer:
The particles of the suspension scatter a beam of light which is passing through it and make its path visible.
IV. Match the following
1. Sodium chloride | a) Impure substance |
2. Milk | b) Suspension solution |
3. Air | c) Pure substance |
d) Mixture |
Answer:
- C
- A
- D
KSEEB Class 8 Science Chapter 16 Additional Questions & Answers
Question 1.
Mention the use of colloids?
Answer:
- homogeneous state for practical applications.
- Preparation of medicines
- Photographic solutions
- Preparation of dyes.
Question 2.
Water is a bipolar molecule. Why?
Answer:
It contains both positive and negative charged ions.
Question 3.
Steam has the capacity to burn skin than boiled water at the same temperature why?
Answer:
Steam particles have more Kinetic energy.