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प्रश्न
Describe a simple experiment to show that l/5th of air is oxygen.
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उत्तर
Aim : To show that l/5th of the air is oxygen.
apparatus required : Glass trough, bell jar, stopper, water, phos-phorus, evaporating dish
PROCEDURE
- a glass trough is filled with water
- A dry evaporating dish containing white phosphorus is made to float on the water.
- This apparatus is covered with a well stoppered bell jar with markings on its side.
- A glowing iron wire is introduced into the bell jar by opening the stopper
- The phosphorus is carefully ignited.
- Re-stopper the apparatus
- The phosphorus bums with a brilliant flame farming dense white fumes of phosphorus pentoxide.
- Soon the burning ceases and the water level starts rising.
- The water occupies approximately l/5th of the original volume, as the fumes dissolve in water.
- Some phosphorus is left unburnt in the dish. The air left behind in the bell jar does not allow the phosphorus to burn.
INFERENCE : The experiment shows that the volume of air oc-cupied by oxygen is 1 /5th.
APPEARS IN
संबंधित प्रश्न
Fill in the blank space by choosing the correct word from the given list.
List: oxygen, carbonic, suIphurUioxide gas, precipitation, helium
_______ gas is used for filling weather observation balloons.
Write down the composition of three main gases present in air by volume.
State the full form of LPG and CNG? How are the two different in their composition?
Fill in the blank
The supporter of combustion in air is _____.
Name the components of air with their approximate percentage by volume in air. Does the percentage by volume of each component remain the same, in the atmosphere of different parts of the world? Explain with reasons.
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 four different properties of a compound and a mixture.
Inhaled air contains a large amount of carbon-di-oxide.
The component of air used by green plants to make their food, is ______.
Assertion: Carbon dioxide occurs as carbonates in nature.
Reason: Carbon dioxide can exist as a liquid at atmospheric pressure.
