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प्रश्न
State the various conditions that favour the process of evaporation.
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उत्तर
The various conditions that favour the process of evaporation are discussed as under :
- Concentration of water vapour in air: (humidity level) : If the water vapour concentration is high in air the evaporation process gets slowed down.
- Pressure : Evaporation takes place faster when pressure is less and vice versa.
- Surface Area: If the surface area is large then evaporation takes place faster.
- Temperature : On increasing the temperature, the rate of evaporation increases.
- Rate offlow of air : If air is moving over the place all the time, then the concentration of water vapour decreases in the surroundings, thus increasing evaporation rate.
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संबंधित प्रश्न
Fill in the blank.
A new substance is formed in a ............... change.
Give two examples of periodic changes.
What are man-made changes ?
Solve this crossword by using the clues that follow-
Across
1. Energy in the form of sunlight is absorbed by the green plants in this process.
4. The reddish-brown substance formed over iron in the presence of oxygen and moisture.
5. This change is permanent and irreversible.
6. The process in which a solid directly changes into gaseous state.
Down
1 . It is the change that takes place in case of swinging pendulum of a clock. –
2. Occurrence of this is a non-periodic change as well as a natural change.
3. It is a physical change.
Which of the following are physical changes and which are chemical changes?
Burning of candle wax, Melting of candle wax, Mixing of iron filings and sand, Burning of wood, Breaking a piece of chalk, Burning a piece of paper, Cutting a piece of paper.
Classify the following as a physical or a chemical change.
Melting of wax
Fill in the blank with the appropriate word of the statement given below:
Germination of seeds is considered a __________ change.
Give a reason why
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When ice melts to form water, change occurs in its
Give two examples for the following case:
Physical changes which are reversible
