Air Around Us
Learn about air, its composition, properties, and importance in our environment. Covers topics like oxygen availability, wind energy, atmospheric gases, respiration, and practical applications of air.
Questions
Plants take in nitrogen from ___________, which is used by plants to make proteins.
- atmosphere
- water
- bacteria in soil
- sunlight
- bacteria in leaves
A weathercock is an instrument used to ____________.
- forecast weather conditions
- tell the direction of wind
- work as an alarm to wake up with the sunrise
- works as an alarm for bad weather conditions
- tells the humidity in air
Why do mountaineers carry oxygen cylinders with them while climbing high mountains?
- At high altitudes, pure oxygen is not available
- Oxygen available is very cold
- There is not sufficient amount of oxygen at higher altitudes
- The atmospheric pressure increases at higher altitudes
- None of these
Which of the following options support all the given statements?
(a) 1% of air is composed of it.
(b) It does not support burning.
(c) Plants need it for photosynthesis.
(d) Humans exhale during respiration.
- Oxygen
- Carbon dioxide
- Nitrogen
- Carbon mono oxide
- Water
Why do earthworms come out of soil, during heavy rainfall?
- To drink water
- To wash their old skin
- To breathe in air
- Their houses in soil get damaged
- Other soil organisms grow and push them out
Which of the statements is / are incorrect?
- Atmospheric oxygen cannot be finished.
- Plants produce more oxygen than what they consume.
- Balance between oxygen and carbon dioxide is maintained by plants and animals.
- Plants are dependent on animals for food.
- Animals are dependent on plants for food.
Which of the following use / s wind energy to move?
- Yatch
- Gliders
- Parachute
- Dispersal of seeds
- All of these
Wind mill cannot be used for which of the following tasks?
- Generating electricity
- Running tube wells
- Running flour mills
- Water aeration
- Dispersal of seeds and pollens
When water is poured on the lump of soil, bubbles are seen coming out of it. What are these bubbles made of?
- Soil organisms breathing out air.
- Soil has air, which gets replaced by water.
- The organisms in the soil decompose and foul CO2 comes out.
- The water poured on it gets evaporated by sunlight.
- None of these
Ramesh dipped the open mouth of his glass bottle, keeping the bottle straight in a bucket filled with water to fill it. What happened?
- His bottle got half filled.
- His bottle was filled completely.
- His bottle was as it is i.e. no water went inside.
- His bottle first got filled but then again the water came out as it was upside down.
- His bottle sank inside.
When water is boiled, bubbles can be seen coming up from the bottom of the pan. Which of the following is present in the water?
- Live microorganisms
- Carbon-dioxide
- Dissolved air in water
- Atmospheric oxygen entering water
- Excess of nitrogen gas in water as in atmosphere
Which of the following statements is / are correct regarding water vapour?
(a) Water vapour is the water that diffuses in the air above its boiling point.
(b) Water vapour is water in its liquid state.
(c) Fog and mist are forms of water vapour.
(d) It is invisible.
- Only a
- Only b
- Only d
- Both a and c
- Both b and c
Factories have long _______________, to prevent us from harmful smoke.
- trees
- boundary walls
- pipe lines
- chimneys
- blast furnaces
What will happen if a child breathes with mouth and not with nose?
- He will breathe in more oxygen.
- Harmful dust particles will also enter.
- Saliva will not let harmful particles enter.
- Teeth will not let enough oxygen enter.
- None of these