RBSE Solutions for Class 6 Science Chapter 15 Air Around Us

Rajasthan Board RBSE Solutions for Class 6 Science Chapter 15 Air Around Us Textbook Exercise Questions and Answers.

RBSE Class 6 Science Solutions Chapter 15 Air Around Us

RBSE Class 6 Science Air Around Us InText Questions and Answers

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Question 1. 
Boojho is asking you, why do you think the policeman is wearing a mask? 

Answer:
Policeman is wearing a mask to protect himself from harmful smoke and dust emitted by vehicles in a crowded area. These harmful smoke and gases may enter into respiratory organs through nose and can cause diseases.

Question 2. 
Paheli wants to know why the transparent glass of windows, if not wiped off regularly appears hazy?
Answer:
Air contains some gases, dust particles, water vapour, etc. These dust particles stick to the transparent glass windows. If we do not wipe off glass windows regularly then there will be a layer of dust particles on a glass. As a result, windows appear hazy.

Question 3. 
Boojho wants to know why during an accident of fire one is advised to wrap a burning object.
Answer:
The woolen blanket cuts off the supply of air. Air (oxygen) helps in burning. Hence, when the supply of oxygen is stopped, the object also stops burning.

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Question 4. 
Here is a question from Paheli, will the tiny bubbles seen before the water actually boils also, appear if we do this activity (activity 5) by reheating boiled water kept in an air tight totftel li yon &o not know the answer you may try doing it and see for yourself.
Answer:
Yes, we know the answers of activity. Bubbles are seen when we heat the water due to the presence of air in it. If water is kept in an air tight bottle after boiling and then it is reheated then no bubbles will be seen due to the absence of air.

RBSE Class 6 Science Air Around Us Textbook Questions and Answers

Question 1. 
What is the composition of air? 
Answer:
Air is a mixture of gases, dust particles and water vapour. It contains nitrogen (78%), oxygfen (21%), carbon dioxide (.03 - .04%) and few other gases like hydrogen, argon, helium, etc. are also present in air. 

Question 2. 
Which gas in the atmosphere is essential for respiration?
Answer:
Oxygen.

Question 3. 
How will you prove that air supports burning?
Answer:
Air has oxygen
1. Fix two small candles of the same length on a table. Lighten up both the candles.
2. Now cover one candle with an inverted glass tumbler.

3. We observed that one candle covered with glass tumbler goes off after sometime whereas the other candle keeps burning.
4. This is because the component of air which supports burning i.e. oxygen, is limited. However, other candle is getting continued supply of air. Thus, this proves that air supports burning i.e. Oxygen gas is necessary for burning.

Question 4. 
How will you show that air is dissolved in water?
Answer:
Air is dissolved in water that can be shown by performing the activity which is as follows:
1. Take some water in a beaker and heat it carefully.
2. Observe the bottom of the surface of the beaker when water starts burning.

3. You will find tiny bubbles. These bubbles are due to the air present in the water.
4. When we heat the water, the air dissolved in it tends to escape out.
5. Hence, the animals and plants live in water get oxygen from water to breathe. 

Question 5. 
Why does a lump of cotton wool shrink in water?
Answer:
Air is trapped among the gaps of light cotton fibres, when the lump of cotton wool is dipped into the water. Water fills into the gaps and displaces air due to which air escapes out from it. The cotton lump becomes heavy and shrinks due to the removal of air gaps. 

Question 6. 
The layer of air around the Earth is known as ...................................
Answer:
Atmosphere.

Question 7. 
The component of air used by green, plants to make their food is ...................................
Answer:
Carbon dioxide.

Question 8. 
List five activities that are possible due to the presence of air. 
Answer:
Five activities that are possible due to the presence of air are:
1. Respiration.
2 Burning of fuel and other substances.
3. Dispersal of seeds and pollen grains.
4. Rotation of windmills.
5. Photosynthesis.

Question 9. 
How do plants and animals help each other in the exchange of gases in the atmosphere?
Answer:
Plants and animals depend on each other for the exchange of gases. Plants take carbon dioxide from the atmosphere for the process of photosynthesis. During this process, oxygen is released. Animals inhale oxygen and give out carbon dioxide to the atmosphere. Hence, plants and animals help each other in the exchange of gases.