Name:_________________________ Date:_______________


Water And Changes Of State (3.1)

A. Write the number of the correct answer in the brackets.
1. For water to have a definite shape and size, it must ________. ()
(1)
(2)
(3)
(4)


have a container
become steam
be distilled
become ice
2. The amount of water vapour in the air is referred to as ________. ()
(1)
(2)
(3)
(4)


temperature
humidity
acidity
heaviness
3. The state of water depends on its ________. ()
(1)
(2)
(3)
(4)


temperature
humidity
volume
size
4. When salt is added to ice, the freezing point of the ice ________. ()
(1)
(2)
(3)
(4)


increases
decreases
remain the same
keep changing
5. Which of the following condition will clothes be dried the quickest? ()
(1)
(2)
(3)
(4)


High humidity, no wind.
High humidity, strong wind.
Low humidity, no wind.
Low humidity, strong wind.
6. The rate of evaporation of a glass of water would be highest when the ________. ()
(1)
(2)
(3)
(4)


water is cold
humidity is high
glass is heated
glass is covered at the top
7. When water is frozen into ice, ________. ()
(1)
(2)
(3)
(4)


heat is extracted from the water
its volume decreases
it is at boiling point
evaporation increases
8. When steam is cooled, it changes into water droplets. This process is known as ________. ()
(1)
(2)
(3)
(4)


freezing
evaporation
condensation
distillation
9. Water freezes at 0 degrees C and boils at 100 degrees C. This statement is only true ________. ()
(1)
(2)
(3)
(4)


at sea-level
in a laboratory
at any place on Earth
when the water is pure
10. When a bespectacled person steps out of an air-conditioned building into the street, his glasses become misty due to ________. ()
(1)
(2)
(3)
(4)



evaporation
freezing
condensation
boiling
B. Write "T" for true and "F" for false.
1. Dry ice can exist in solid, liquid or gaseous state.

()
2. The rate of evaporation depends on the exposed surface area of the water.

()
3. Evaporation takes place at temperatures lower than boiling point.

()
4. Ice can be changed into water vapour without first becoming water.

()
5. When clouds fall as rain, the process of condensation has taken place.

()
6. The weight of water, whether in solid, liquid or gas is the same.

()
7. Plants only give off oxygen, they do not give off water vapour.

()
8. We give off water vapour through the pores on our skin.

()
9. The process by which plants give off water vapour is known as perspiration.

()
10. In cold countries, we may get snow instead of rain from the clouds.


()
C. Fill in the blanks with the most suitable word.
1. When water changes to steam, its state changes from __________ to __________.

2. Water ---> water vapour ---> clouds ---> rain. This is a __________ __________.

3. When water boils, we can see ____________ escaping from the water.

4. Hot water vapour from boiling is called ____________.

5. 0 degree C is known as the ____________ point of ice or ____________ point of water.


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