Evaporation

Q. Evaporation only takes place at boiling point of a liquid.

1. True
2. False

Q.

Ice pellets are also known as ___ .

1. Sleet

2. Photochemistry

3. Twister

4. Slots

Q. Which of the following scenario is the best for drying our clothes the quickest, given that clothes dry due to evaporation?

1. A windy day in desert region.
2. A windy day in coastal region.
3. A calm day in desert region.
4. A calm day in coastal region.

Q. Question 26
Comment on the following statements:
(a) Evaporation produces cooling.
(b) Rate of evaporation of an aqueous solution decreases with increase in humidity.
(c) Sponge though compressible is a solid.

Q.

Statement 1: Evaporation causes cooling of the liquid.
Statement 2: During evaporation, the surface molecules with high kinetic energy gets evaporated.

1. Statement 1 and statement 2 both are correct and statement 2 is the correct explanation of statement 1.
2. Statement 1 and statement 2 both are correct and statement 2 is not the correct explanation of statement 1.
3. Statement 2 is correct and statement 1 is wrong.
4. Statement 1 is correct and statement 2 is wrong.

Q. The process of conversion of water into its vapour is called _______________.

1. evaporation
2. condensation
3. boiling
4. melting

Q.

Name the general mode of heat transfer in [2 MARKS]
a) Solids
b) Liquids and gases.

Q. The phenomenon of change of a liquid into the gaseous state at any temperature below its boiling point is called :

1. sublimation
2. evaporation
3. boiling
4. cooling

Q. The phenomenon of changing liquid into vapours at a temperature its boiling point is called evaporation.

Q. Why does the amount of water vapour decrease rapidly with altitude?

Q. Question 9
Which condition out of the following will increase the evaporation of water?
(a) Increase in temperature of water
(b) Decrease in temperature of water
(c) Less exposed surface area of water
(d) Adding common salt to water

Q. 2 kg of water at 100°c is contained in a vessel of negligible heat capacity. In to this water is added 3 kg of ice at 0°c .Calculate the amount of water at 0 °c at the end of experiment? ( Take sp. heat capacity of water 4.2 ×10 raise to the power 3 J and sp. latent heat of ice 336×10 raise to the power 3 J)

Q. When Rahul was suffering from fever, his mother placed a wet cloth on his forehead for comfort. Which of the following processes aids this?

Q. 200 g of ice at 0degree Celcius converts into water at 0degree Cecius in 1 minute when heat is supplied to it at a constant rate. In how much time 200g of water at 0degree Celcius will change to 20degree Celcius? Take specific latent heat of ice=336 J g-1.

Q.

Which of the following change occurs during evaporation?

1. Solid to liquid

2. Liquid to gas

3. Solid to gas

4. Liquid to solid

Q. Assertion :Salt water is sprinkled in cold countries to remove ice on roads. Reason: Melting point increases by addition of soluble impurities.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Assertion is incorrect but Reason is correct

Q. You want to wear your favourite shirt to a party, but the problem is that it is still wet after a wash. What steps would you take to dry it faster?

Q.

The vapour pressure of a liquid at any temperature is defined as the pressure exerted by the vapour in equilibrium with the liquid at that temperature. T/F

1. False

2. True

Q. 1.6 kg of boiling water at 100°c is poured into 2 kg of crushed ice at 0°c, such that final temp. recorded is 0°c. Calculate the specific latent heat of ice? ( sp. latent heat of water = 4200 J/kg/K )