Science - Air around us
Exam Duration: 45 Mins Total Questions : 30
Which of the following statements is true regarding the earth's atmosphere?
- (a)
It gets denser with an increase in the altitude.
- (b)
It gets thinner with an increase in the altitude.
- (c)
It remains the same.
- (d)
It contains no solid particles.
Which of the following plays a very important role in the oxygen cycle?
- (a)
Birds
- (b)
Animals
- (c)
Plants
- (d)
Soil
Which of the following can show the direction of the wind?
- (a)
An anemometer
- (b)
A wind mill
- (c)
A windvane
- (d)
A barometer
Which of the constituents of air on increasing, causes global warming?
- (a)
Nitrogen
- (b)
Oxygen
- (c)
Inert gases
- (d)
Carbon dioxide
Plants require nitrogen for
- (a)
reproduction.
- (b)
photosynthesis.
- (c)
transpiration.
- (d)
their growth.
Breathing of air through our mouth is not hygienic because
- (a)
dust particles will enter our lungs.
- (b)
we will inhale more carbon dioxide.
- (c)
our throat will become sore.
- (d)
we will easily catch cold.
Which of the following enables us to drink a liquid through a straw?
- (a)
Humidity
- (b)
Temperature
- (c)
Atmospheric pressure
- (d)
Composition of air
Which of the following is combustible?
- (a)
Oxygen
- (b)
Carbon dioxide
- (c)
Hydrogen
- (d)
All of these
Which of the following is NOT associated with air?
- (a)
Having a campfire
- (b)
Flying a paper aeroplane
- (c)
Blowing out candles on a birthday cake
- (d)
Sunbathing at the beach
What can be said about the nature of air?
- (a)
Air is heterogeneous
- (b)
Air is a compound
- (c)
Air is homogeneous
- (d)
Air is an alloy
Wind mills produce energy and convert it into
- (a)
heat energy
- (b)
light energy
- (c)
sound energy
- (d)
electrical energy
What is the percentage of carbon dioxide present in air?
- (a)
0.3%
- (b)
0.03%
- (c)
0.003%
- (d)
1%
In the given figure, a burning candle is kept in the trough containing water. It is put off after some time when covered by an inverted gas jar.
What can be concluded from the above activity?
- (a)
Oxygen is l/5th the volume of air.
- (b)
The ratio of oxygen and nitrogen in air is 1:4.
- (c)
Oxygen is required for burning the candle.
- (d)
All of the above
Which of the following gases is the component of air?
- (a)
Hydrogen
- (b)
Oxygen
- (c)
Nitrogen
- (d)
All of the above
Which of the following is the most abundant element in the earth's crust?
- (a)
Nitrogen
- (b)
Oxygen
- (c)
Silicon
- (d)
Hydrogen
In which of the following processes do plants require carbon dioxide?
- (a)
Photosynthesis
- (b)
Transpiration
- (c)
Growth
- (d)
Reproduction
Carbon dioxide gas can be tested by using
(i) blue litmus paper.
(ii) lime water.
(iii) burning splinter
- (a)
Only (i) and (ii)
- (b)
Only (ii) and (iii)
- (c)
Only (i) and (iii)
- (d)
(i), (ii) and (iii)
Which of the following gases in air helps burning?
- (a)
Oxygen
- (b)
Nitrogen
- (c)
Carbon dioxide
- (d)
Methane
In an experiment shown by the class teacher, the side of the ruler which holds the inflated balloon dips as compared to the balloon without air.
What is the conclusion drawn from this experiment?
- (a)
Balloon with air has greater force of gravity.
- (b)
Air has definite mass.
- (c)
Masses of the balloons are different.
- (d)
Balloon has more matter than air.
Which of the following can reduce air pollution on roads?
- (a)
The widening of roads.
- (b)
Having more traffic lights on roads.
- (c)
Having less traffic lights on roads.
- (d)
Reducing the number of vehicles on roads.
What is the purpose of a weather cock?
- (a)
It tells us about the daily weather.
- (b)
It tells us about start of the morning.
- (c)
It shows us the direction in which the wind is moving at the place it is placed.
- (d)
All of these
Mountaineers carry oxygen cylinders while climbing high mountains. This is because
- (a)
It is difficult to breathe at high altitudes.
- (b)
The air is thinner at higher reaches of the mountains.
- (c)
As we move up the oxygen present in the air reduces.
- (d)
All of these.
An experiment was set up by placing a burning candle in a trough of water. A large graduated cylinder was inverted on it.
What will happen to the burning candle as the jar is inverted on it?
- (a)
It will be extinguished immediately.
- (b)
It will continue to burn indefinitely
- (c)
It will burn for some time and then blow out.
- (d)
The melted wax will be seen on the inner sides of the cylinder
An experiment was set up by placing a burning candle in a trough of water. A large graduated cylinder was inverted on it.
Why does the burning candle get extinguished?
- (a)
The cylinder is made up of glass
- (b)
The candle was not of good quality
- (c)
The oxygen in the cylinder has been used up
- (d)
All of these
An experiment was set up by placing a burning candle in a trough of water. A large graduated cylinder was inverted on it.
Which new gas will increase in amount in the cylinder?
- (a)
nitrogen
- (b)
oxygen
- (c)
carbon dioxide
- (d)
all of these
An experiment was set up by placing a burning candle in a trough of water. A large graduated cylinder was inverted on it.
What will happen to the water level in the trough?
- (a)
It will decrease
- (b)
It will increase
- (c)
It will remain the same.
- (d)
Can't say.
Our body tries to protect us from dust particle
- (a)
trapping them in the mucus of the nostrils
- (b)
trapping them in the fine hair of the nostrils
- (c)
both 'a' and 'b'.
- (d)
none of these
In dry summer months, the transparent glass of windows appears hazy when not wiped off regularly. This is because of
- (a)
water vapour .
- (b)
bad quality of glass.
- (c)
nitrogen.
- (d)
dust.
Garima took a lump of dry soil in a beaker. She added some water to it. She will find that
- (a)
all the soil dissolves in water.
- (b)
bubbles will come out of the soil
- (c)
some of the soil will dissolve in water
- (d)
none of these will happen
A lump of cotton wool shrinks in water because
- (a)
cotton is lighter
- (b)
cotton is heavier
- (c)
cotton wool is stretchable
- (d)
water displaces the air present in cotton wool.