Advertisements
Advertisements
प्रश्न
How will you demonstrate that water vapour is present in air ?
उत्तर
The presence of water vapour in air can be shown by the following experiment:
Take a steel tumbler and put some well-crushed ice into it and wipe its surface with a clean dry cloth, so as to make its surface completely dry. Allow it to stand for 5 minutes. A large number of drops of water vapour appear on the outer surface of the tumbler. This happens because the air around the steel tumbler contains water vapour in it. When this water vapour comes into contact with the cold outside surface of the steel tumbler, it condenses to form tiny drops of liquid water. The formation of tiny drops of water outside the steel tumbler containing crushed ice, shows the presence of water vapour in air.
APPEARS IN
संबंधित प्रश्न
How does water kept in an earthen pot (matka) become cool during summer?
What is evaporation?
Why are volatile liquids such as alcohol and spirit stored in tightly closed bottles?
Explain why in hot summer days water remains cool in earthen pots.
The ______ of air is dependent on the temperature of air.
How is humidity measured?
Evaporation of water from lakes and river ______.
Comment on the following statements:
Evaporation produces cooling.
When lemon juice is mixed with soda water, they produce brisk effervescence.
The process of evaporation is not a good technic to separate salt from seawater give a reason.