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प्रश्न
How do astronauts breathe when they go beyond the earth’s atmosphere?
उत्तर
It is because nitrogen tires hold pressure longer as compared to compressed air. Nitrogen gas in the tire escapes more slowly than compressed air does.
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संबंधित प्रश्न
Name and briefly explain four ways by which pollution of air caused by humans is minimised.
Classify Calcium oxide. Also give a balanced equation to prepare it.
Fill in the blank space by choosing the correct word from the given list.
List: sulphurous, nitric acid, red lead oxide paint, oxygen, phosphoric
Sulphur dioxide gas dissolves in water to form ___________ acid.
Match the statements in List 1 with the correct answers in List 2
| List 1 | List 2 | ||
| 1 | An impurity in air | A | Water vapour |
| 2 | The component of air which supports combustion | B | Respiration |
| 3 | The inert component in the air slightly soluble in water | C | Rare gases |
| 4 | The component of air which minimizes the rate of evaporation | D | Sulphur dioxide |
| 5 | The process which involves oxidation of food substance in living organisms | E | Helium |
| 6 | The component of air which finds application in observation balloons | F | Carbon dioxide |
| 7 | The process which involves oxidation of substances, liberating heat and light energy | G | Combustion |
| 8 | The component of air which is heavier than air and fairly soluble in water | H | Nitrogen |
| 9 | The process by which atmospheric carbon dioxide is absorbed by plants resulting in the formation of carbohydrates | I | Photosynthesis |
| 10 | The component of air which is lighter than air and less than 1% in air | J | Oxygen |
State whether the following statement is ‘true’ or ‘false’. If false write the correct statement.
The mesosphere in the atmosphere, contains most of the air, fit for respiration
Why do we see the sky and air clear and clean after rainfall?
Explain why during an incident of fire, one is advised to wrap a woollen blanket over a burning object.
______ is necessary for all acids.
Boojho took an empty plastic bottle, turned it upside down, and dipped its open mouth into a bucket filled with water. He then tilted the bottle slightly and made the following observations.
(i) Bubbles of air came out from the bottle.
(ii) Some water entered the bottle.
(iii) Nitrogen gas came out in the form of bubbles and oxygen got dissolved in water.
(iv) No bubbles formed, only water entered the bottle.
Which observations is/are correct?
Observe the picture given in Fig. carefully and answer the following questions.
Can you comment on the air quality of the place shown in Fig?
