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प्रश्न
Give a reason why water droplets appear on the outer surface of a tumbler containing ice.
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उत्तर
Water vapour present in air, condenses on the cooler surface of the tumbler. Hence they condenses into tiny water droplets.
संबंधित प्रश्न
Answer the question put against the following constituents of air :
Carbon dioxide : “Although carbon dioxide plays no role in respiration, all life would come to an end if there is no carbon dioxide in air.” Support this statement with relevant facts.
Statement given below is incorrect. Write the correct statement :
Potassium nitrate on strong heating decomposes into potassium nitrite and nitrogen gas.
Tick (√ ) the most appropriate answer.
Magnesium burns with a dazzling white flame to form magnesium oxide, a powdery mass. The colour of magnesium oxide is :
Fill in the blanks
Oxygen is used in ___________the food to get _______.
The diagrams below represents an experiment to show the presence of a component of air.
- State why air is sucked from – outlet ‘B’ and not from outlet “A”
- State why the air is sucked ‘slowly’ from the outlet “B”
- State the observation seen after completion of the experiment.
- State the reason for the above observation seen.
- Name another component which if present in air as a pollutant would have given a similar observation
How will you prove that soil contains air in it?
Explain why during an incident of fire, one is advised to wrap a woollen blanket over a burning object.
Arrange the following statements in correct sequence
- Plants manufacture food by a process called photosynthesis.
- Plants require energy for their growth.
- Plants take in oxygen and release carbon dioxide just as animals.
- Plants take carbon dioxide from the atmosphere, use chlorophyll in the presence of sunlight and prepare food.
- Such oxygen is available to animals and human beings for breathing.
- During this process, oxygen is released by plants.
The composition of air changes slightly from place to place. Give examples.
Write the reaction of carbon dioxide with lime water.
