Melting and Boiling Point of Water

Q. Among the following temperature, motion of water particles will be highest at ____.

1. $0{}^0$C
2. $100{}^0$C
3. $10{}^0$C
4. $50{}^0$C

Q. Anita puts an ice tray filled with water inside the freezer of a refrigerator. After sometime water changes to ice. What is the process involved here?

1. Boiling
2. Condensation
3. Freezing
4. Sublimation

Q. A substance X has the following properties:
i) Melting point: $80{}^{o}C$
ii) Boiling point $150{}^{o}C$
iii) Water insolule
Which method of separation would be best fit to obtain pure X from a mixture of X and water?

1. Evaporation
2. Fractional distillation
3. Crystallisation
4. Filtration

Q.

What is a bulk phenomenon in terms of boiling

Q. When the ice cubes are heated, the temperature at the melting point until the ice melts completely.

1. increases
2. decreases
3. remains constant

Q. A glass filled with ice cubes was kept on a table. After a while, water droplets appeared on its outer surface. Identify the correct statements.

1. This phenomenon is known as evaporation.
2. This proves that water vapours are present in the air.
3. This phenomenon is known as solidification.
4. This phenomenon is known as condensation.

Q.

Which of the following is an example of drying agent?

1. Quick lime
2. Fused calcium chloride
3. Concentrated sulphuric acid
4. All of the above

Q. Gases can be liquified by:

1. increasing temperature
2. decreasing pressure
3. increasing pressure
4. decreasing temperature

Q.

The density of brass Is $8.4\raisebox{1ex}{$g$}\!\left/ \!\raisebox{-1ex}{$c{m}^3$}\right.$. What Do You Mean By This Statement?

Q.

explain briefly, how gases can be liquified?

Q. Which of the following is correct for processes involved in state change?

1. Boiling is same as condensation
2. Evaporation is the opposite of condensation
3. Freezing is the opposite of melting
4. Freezing is same as melting

Q. Match Column I with Column II and select the correct option from the codes given below

Column I	Column II
(a) Drying of clothes on a windy day	(i) Time taken for evaporation increases
(b) Liquefaction of gases	(ii) Decreasing pressure and increasing temperature
(c) Change in state of dry ice from solid to gas	(iii) Increasing pressure and decreasing temperature
(d) Less cooling effect of sweating in coastal areas	(iv) Rate of evaporation increases

1. a - (iv), b - (iii), c - (i), d - (ii)
2. a - (i), b - (ii), c - (iii), d - (iv)
3. a - (iii), b - (iv), c - (ii), d - (i)
4. a - (iv), b - (iii), c - (ii), d - (i)

Q.

Define the following process involved in the change of state of a substance- vapourasation

Q. In the destructive distillation of coal, at 443-503 K temperature, a middle oil or carbolic oil fraction is obtained. This fraction contains :

1. Phenol
2. Xylene
3. Naphthalene
4. Benzene

Q. The S.I. unit of density is _____.

1. $g/m^3$
2. $kg/m$
3. $kg/m^3$
4. $kg/m^2$

Q. A larger surface area results in a greater cooling effect.

1. True
2. False

Q.

Which of the following option correctly differentiates between evaporation and boiling?

1. Evaporation takes place only at boiling point, i.e., ${100}^{\circ }C$.

2. Evaporation takes place at temperatures below the boiling point.

3. Evaporation takes place only above boiling point.

4. Both evaporation and boiling are same.

Q.

Define Solublity