log up log in
ncert help

NCERT Solutions, CBSE Sample paper, Latest Syllabus, NCERT Books, Last Year Question Papers and Many More ...

CBSE Video lectures for download

     

=In text questions page number 3

=In text questions page number 6

=In text questions page number 9

=In text questions page number 10

 

In text questions page number 6

In text questions page number 6


Question 1. The mass per unit volume of a substance is called density. (Density = mass/volume).
Arrange the following in order of increasing density – air, exhaust from chimneys, honey, water, chalk, cotton and iron.
Answer:
Arrangement of the above matters in order of increasing density
Air<exhaust from chimney<cotton<water<honey<chalk<Iron

Question 2. (a) Tabulate the differences in the characteristics of states of matter.
(b) Comment upon the following:
rigidity, compressibility, fluidity, filling a gas container, shape, kinetic energy and density.
Answer:
(a)

S.NO

Property

Solid

Liquid

Gases

1.

Shape

They Have definite shape

They do not have definite shape

They do not have definite shape

2.

Volume

They have definite volume

They do not have definite volume

They do not have definite volume

3.

Density

They have high density.

Liquids have less density than solids.

Liquids have least density.

4.

Kinetic energy of particles.

Least

More than solids

Maximum

5.

Compressibility

Negligible

Low

High


Rigidity: It is the property of matter to resist the change of its shape.
Compressibility: It is the property of matter in which its volume is decreased by applying force.
Fluidity: It is the ability of matter to flow.
Filling a gas container: On filling a gas takes the shape of the container.
Shape: Having definite boundaries.
Kinetic energy: It is the energy possessed by the particles of matter due to its motion.
Density: It is the ratio of mass with per unit volume

Question 3. Give reasons                                                                                           
(a) A gas fills completely the vessel in which it is kept.                                 
(b) A gas exerts pressure on the walls of the container.                               
(c) A wooden table should be called a solid.                                                 
(d) We can easily move our hand in air but to do the same through a solid block of wood we need a karate expert.
Answer:

(a) A gas fills completely the vessel in which it is kept because the particles of gas move freely and acquire the shape of the container.
(b) A gas exerts pressure on the walls of the container because particles of gas move freely and randomly due to which they hit the boundaries of the container and exert the force on its wall.
(c) A wooden table has a definite shape and definite volume and hence it is called solid.
(d) We can easily move our hand in air but to do the same through a solid block of wood we need a karate expert because there is lot of empty space between the particles of gas but it not so in case of solids.

Quesiton 4. Liquids generally have lower density as compared to solids. But you must have observed that ice floats on water. Find out why.
Answer:
Ice in fact it is solid but it has cage like structure and hence its molecules have more empty space as compared to water so it has smaller density then water and hence floats on water.



Open your video in VLC player or add '.mp4' extension at end of the video



In text questions page number 6

Please Click on G-plus or Facebook
   



Please send your queries at contact ncerthelp@gmail.com

 

Every effort has been made to ensure accuracy of data on this web site. We are not responsible for any type of mistake in data.
All pdf files or link of pdf files are collected from various Resources Or sent by Students. If any pdf file have any copyright voilation please inform us we shell remove that file from our website.Thanks