Page 74 - Active Science 5 Ebook and Activity

Other Gases
Other than oxygen, nitrogen and carbon dioxide, some other gases are also present in

the atmosphere. Helium, neon, hydrogen, argon, krypton and ozone are some other gases
present in the atmosphere.

Air also contains water vapour, dust and smoke. Water Factual Study
present in seas, oceans, lakes, etc., evaporates with the heat Air pollution is a major
of sun. And this water present in air is called humidity. It cause of lung diseases like

tells about the amount of water vapour in air. This makes the bronchitis, asthma and
weather humid. lung cancer.

Let’s Recapitulate

Write the appropriate word/words to complete each statement.
1. Air is a ______________ of gases.

2. The process of converting a liquid into its vapour is called ______________.
3. Oxygen ______________ burning.

4. The gas present in air in the greatest amount is ______________.

P roperties of Air

1. Air has weight.

Activity 6.2

Aim : To prove that air has weight.

Materials Required : Two deflated footballs, beam
balance

Procedure : • Take two deflated footballs of

the same size.

• Weigh them on a beam
balance. Inflate one of them.

• Weigh them again. Which
football is heavier?

Observation : The inflated football is heavier. This is because the inflated football

has air inside it.

Conclusion : The experiment shows that air has weight.

74 Active Science-5