Page 239 - New Medley 4 Semester 2 PDF (Merged)

D. Answer these questions.

1. What is matter?
2. What are molecules?

3. What is the difference between the molecules of water and molecules of chlorine
gas?
4. How are you able to smell an agarbatti even if it is lighted in the other corner of
a room?

5. Define evaporation. Name a phenomenon opposite to evaporation.
6. What is a solution?
7. Draw diagrams to show the arrangement of molecules in solids, liquids and gases.

Think and Answer • Critical Thinking

1. Circle the odd one out and give reason for your choice.
(a) Sugar, Salt, Chalk, Water
(b) Oxygen, Hydrogen, Chlorine, Ice
(c) Petrol, Butter, Oil, Milk

(d) Pencil, Milk, Common salt, Sugar
2. A balloon is attached to the mouth of a bottle containing club soda. The bottle is then
shaken gently and left to stand for some time. The balloon gets inflated. Why?

3. When sugar is dissolved in water, the volume of water does not rise. Why?

Let Us Do S E L Self-Management • Creativity/Hands-on Learning

Make your sugar crystals.
l Take a glass tumbler and half fill it

with hot water. Slowly mix as much
sugar as possible in it. Keep adding
sugar until you have a thick syrup.
l Tie a paper clip with a piece of

thread and suspend it in the tumbler.
Make sure that the paper clip does
not touch the bottom. Leave the
tumbler where it won’t be disturbed

and cover it properly to keep the
dust away.
l After two days, crystals will begin
to form around the paper clip and thread.

l Take a magnifying glass and look at the crystals. Try to recognise their shapes.

237