Cooling from Evaporation

Q.

Evaporation causes cooling. Explain why?

Q.

During summer, water kept in an earthen pot becomes cool because of the phenomenon of _______

1. Diffusion

2. Transpiration

3. Osmosis

4. Evaporation

Q.

What is a desert cooler?

Q.

Why should we wear cotton clothes in summer?

1. Cotton provides better air circulation.

2. Cotton is a good absorber.

3. Cotton provides better air circulation and a good absorber.

4. There are more patterns availible.

Q.

Which one of the following sets of phenomena would increase on raising the temperature?

1. Diffusion, evaporation, compression of gases

2. Evaporation, compression of gases, solubility

3. Evaporation, diffusion, expansion of gases

4. Evaporation, solubility, diffusion, compression of gases

Q.

How does perspiration or sweating help keep our body cool on a hot day?

Q.

Why dogs generally hang out their tongue in summer

Q. Which of the following is not an example of a chemical reaction?

1. Burning of firewood
2. Rusting of iron rod
3. Curdling of Milk
4. Melting of ice

Q.

Why do we feel a cold sensation if we put nail polish remover on our skin?

1. Acetone freezes on our hand surface.
2. Acetone evaporates rapidly, leaveing a cooling sensation.
3. Acetone starts boiling taking heat from the hand.
4. Acetone melts on our hand.

Q. Does the temperature of liquid change during evaporation?

Q.

We should wear cotton clothes in hot summer days to keep cool and comfortable. Why?

Q.

At what temperature does evaporation of a liquid takes place?

Q. How can we separate sugar and water?

Q.

Evaporation of a liquid at room temperature leads to a___ effect.

Q.

During evaporation, the liquid absorbs heat from the surroundings and causes the cooling in the surroundings.

1. True
2. False

Q.

What type of clothes should we wear in summer? Why?

Q.

When we boil salt and water we get salt back so by doing the same process why we cant get sugar back?

Q.

Do we sweat more on dry day or humid day ?? Justify your answer.

Q.

Salt can be recovered from its solution by evaporation. Suggest some other technique for the same?

Q. Before the doctor gives an injection, he applies spirit at that spot. At that time our skin feels very cool because:

1. the spirit evaporates using the heat from our body.
2. the spirit kills the bacteria present on the skin.
3. the spirit is at low temperature.
4. the spirit loses its heat when it is taken out of the bottle.

Q.

How can clothes gets dry faster by the process of evaporation please explain to me, in a short and easy way....so that I can learn it faster

Q.

Water kept in an earthen pot become cool during summer. why?

Q.

difference between crystalisation and evaporation? can we get pure salt only by evaporation?

Q.

Does the water kept in an earthen pot become cool during summer.

Give reasons

Q.

Water kept in sunlight gets heat from sun and is evaporated. But how does water kept under the shade of a tree also get evaporated? Explain.

Q. What are the steps we can do for drying wet clothes

Q. The bulb of thermometer when dipped in petrol and taken out, the level of the mercury thread in the thermometer

1. 
   starts falling
2. 
   starts rising
3. 
   remains at the same level
4. 
   initially falls and then rises

Q.

We heat the ink to obtain the coloured component (dye) in a watch glass (similar to a glass cup). The process involved here is ______ and the component removed from ink-solution is ________.

1. Condensation, oil

2. Melting, water vapour

3. Sublimation, water vapour

4. Evaporation, water

Q. Why do we sweat more on a humid day than on a hot dry day?

Q. Why we should wear cotton clothes in summer and atomic mass