The Class 8 Physics Chapter 1, matter, deal with what the constituents of a matter are. BYJU’s provides the solutions for ICSE Selina Class 8 Physics Chapter 1- Matter in PDF format so that the students can download these solutions for free.
ICSE Selina Class 8 Physics Chapter 1, matter Solutions covers all the chapters from the class 8 Selina publication. The experts at BYJU’S make sure that no chapter is left unsolved. The ICSE toppers of previous years recommend these solutions for the efficient preparation of the ICSE Class 8 Physics exam.
A matter is anything that has mass and occupies space. The building blocks of matter are called elements. Â More than 100 naturally occurring elements are present. Atom is the smallest unit of an element. A collection of atoms of either similar or different elements forms a molecule. The smallest unit of matter is known as a molecule, and it exists freely in nature. These molecules are in a continuous state of motion and hence possess kinetic energy.
The kinetic particle theory describes the features of the various states of matter. The amount of energy varies according to the particles in solids, liquids and gases. They move in different ways and are arranged differently.
Download ICSE Class 8 Physics Selina Solutions PDF for Chapter 1 Matter
A. Objective Questions
1. Write true or false for each statement
(a) The temperature of a substance remains unaffected during its change of state.
Answer: True.
(b) Ice melts at 100°C.
Answer: False.
(c) Water at 100°C has more heat than the steam at 100°C.
Answer: False.
(d) Evaporation of a liquid causes cooling.
Answer: True.
(e) Water evaporates only at 100°C.
Answer: False.
(f) Boiling takes place at all temperatures.
Answer: False.
(g) Evaporation takes place over the entire mass of the liquid.
Answer: False.
(h) The process of a gas converting directly into gas is called vaporization.
Answer: False.
(i) At high altitudes, water boils above100°C.
Answer: False.
(j) The melting point of ice is 0°C.
Answer: True.
Question 2.
Fill in the blanks
(a) Evaporation takes place at all temperature.
(b) Freezing process is the just reverse of melting.
(c) Sublimation is a process that involves the direct conversion of a solid into its vapour on heating.
(d) The temperature at which a solid convert into a liquid is called it’s melting point.
(e) The smallest unit of matter that exists freely in nature is called a molecule.
(f) Molecules of a substance are always in a state of motion and so they possess kinetic energy.
(g) Intermolecular space is maximum in gases less in liquids and the least in solids.
(h) The intermolecular force of attraction is maximum in solids, less in liquids and the least in gases.
Question 3.
Match the following:
Column AÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Column B
(a) Molecules               (i) water boils
(b) 100°C                  (ii) evaporation
(c) 0°C                     (iii) changes from solid to gas
(d) At all temperatures       (iv) matter
(e) Camphor                (v) water freezes
Solution:
Column AÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Column B
(a) Molecules              (iv) matter
(b) 100°C                 (i) water boils
(c) 0°C                    (v) water freezes
(d) At all temperatures     (ii) evaporation
(e) Camphor              (iii) changes from solid to gas
Question 4.
Select the correct alternative
(a) The inter-molecular force is maximum in
1. Solids
2. Gases
3. Liquids
4 none of the above
Solution: 1. Solids
(b) The inter-molecular space is maximum in
1. liquids
2. solids
3. gases
4. none of the above
Solution: 3. Gases
(c) The molecules can move freely anywhere in
1. gases
2. liquids
3. solids
4. none of the above
Solution: 1. Gases
(d) The molecules move only within the boundary of
1. liquids
2. gases
3. solids
4. none of the above
Solution: 1. Liquids
(e) The temperature at which a liquid gets converted into its vapour state is called its
1. melting point
2.boiling point
3. dewpoint
4. freezing point.
Solution: 2. Boiling point
(f) Rapid conversion of water into steam is an example of
1. evaporation
2. freezing
3. melting
4. vapourization
Solution: 4. Vapourization
(g) Evaporation takes place from the
1. the surface of the liquid
2. throughout the liquid
3. mid-portion of the liquid
4 bottom of the liquid.
Solution: 1. surface of the liquid
(h) Boiling takes place from the
1. the surface of the liquid
2. throughout the liquid
3. mid-portion of liquid
4. none of the above.
Solution: 2. throughout the liquid
Comments