Question Bank Solutions for CBSE Class 9 - CBSE - Science

Make a comparison and write down ways in which plant cells are different from animal cells.

What is osmosis?

Carry out the following osmosis experiment:

Take four peeled potato halves and scoop each one out to make potato cups. One of these potato cups should be made from a boiled potato. Put each potato cup in a trough containing water. Now,

(a) Keep cup A empty

(b) Put one teaspoon sugar in cup B

(c) Put one teaspoon salt in cup C

(d) Put one teaspoon sugar in the boiled potato cup D.

Keep these for two hours. Then observe the four potato cups and answer the following:

(i) Explain why water gathers in the hollowed portion of B and C.

(ii) Why is potato A necessary for this experiment?

(iii) Explain why water does not gather in the hollowed out portions of A and D.

Which of the following materials fall in the category of a “pure
substance”?

(a) Ice

(b) Milk

(c) Iron

(d) Hydrochloric Acid

(e) Calcium oxide

(f) Mercury

(g) Brick

(h) Wood

(i) Air

Classify the following into elements, compounds and mixtures:

(a) Sodium

(b) Soil

(c) Sugar solution

(d) Silver

(e) Calcium carbonate

(f) Tin

(g) Silicon

(h) Coal

(i) Air

(j) Soap

(k) Methane

(l) Carbon dioxide

(m) Blood

Which type of cell division is required for growth and repair
of body and which type is involved in formation of gametes?

What are the conditions for 'something' to be called 'matter'?

Name two processes which provide the best evidence for the motion of particles in matter.

What is the scientific name of particles which make up mater?

Out of solids, liquids and gases, which one has :

1. maximum movement of particles ?
2. maximum interparticle attractions ?
3. minimum spaces between particles ?

Fill in the following blank with suitable words :

The best evidence that the particles of matter are constantly moving comes from the studies of ................. and ...................

State two characteristics of matter demonstrated by Brownian motion.

Name the scientist who studied the movement of pollen grains suspended in water through a microscope. What is this phenomenon known as?

When a crystal of potassium permanganate is placed in a beaker, its purple colour spreads throughout the water. What does this observation tell us about the nature of potassium permanganate and water?

When a gas jar containing air is inverted over a gas jar containing bromine vapour, the red-brown bromine vapour diffuse into air. Explain how bromine vapour diffuse into air.

Describe in your own words, what happens to the particles when salt dissolves in water.

Honey is more viscous than water. Can you suggest why?

Explain why air is used to inflate tyres.

Explain why steel is used to make railway lines.

Define matter. Give four examples of matter.