Unit
# 3…….. M.C.Qs on Liquid State
1. The attractive forces which exist between
the individual particles (atoms, molecules or ions) are called:
|
(a)
|
Intermolecular forces
|
(b)
|
Intramolecular forces
|
|
(c)
|
Electrostatic forces
|
(d)
|
Hydrogen bonding
|
2. Which
one of the following is an intermolecular force?
|
(a)
|
Dipole-dipole force
|
(b)
|
London forces
|
|
(c)
|
Hydrogen bonding
|
(d)
|
All of the above
|
3. The
weak electrostatic attraction between two polar molecules is called:
|
(a)
|
Dipole-dipole force
|
(b)
|
London forces
|
|
(c)
|
Hydrogen bonding
|
(d)
|
All of the above
|
4. Which
type of molecules possesses dipole-dipole interaction?
|
(a)
|
Dipole-dipole force
|
(b)
|
London forces
|
|
(c)
|
Hydrogen bonding
|
(d)
|
All of the above
|
5. The electrostatic force of attraction
between a hydrogen atom bonded to a small, highly electronegative atom and the
lone electron pair of a neighbouring electronegative atom is called:
|
(a)
|
Polar molecules
|
(b)
|
Ionic compounds
|
|
(c)
|
Non-polar molecules
|
(d)
|
All of the above
|
6. Which
does not affect the rate of evaporation?
|
(a)
|
Temperature
|
(b)
|
Surface area
|
|
(c)
|
Intermolecular forces
|
(d)
|
pressure
|
7. The amount of heat required to convert one
gram of a liquid into its vapours at its boiling point without change of temperature is called:
|
(a)
|
Specific heat
|
(b)
|
Latent heat of fusion
|
|
(c)
|
Latent heatof vaporization
|
(d)
|
Fluidity
|
8. Molar
heat of vaporization in presence of hydrogen bonding:
|
(a)
|
Slightly decreases
|
(b)
|
Decreases
|
|
(c)
|
Increases
|
(d)
|
Remains same
|
9. Molar
heat of vaporization in presence of hydrogen bonding:
|
(a)
|
Slightly decreases
|
(b)
|
Decreases
|
|
(c)
|
Increases
|
(d)
|
Remains same
|
10. Which
one of the following liquid possesses high vapour pressure?
|
(a)
|
Volatile liquids
|
(b)
|
Non-volatile liquids
|
|
(c)
|
Polar liquids
|
(d)
|
None of the above
|
11. The
vapour pressure of a liquid increases with the rise of:
|
(a)
|
Mass
|
(b)
|
Volume
|
|
(c)
|
Temperature
|
(d)
|
All of them
|
12. The temperature at which vapour pressure of
a liquid becomes equal to the atmospheric pressure is called:
|
(a)
|
Boiling point
|
(b)
|
Melting point
|
|
(c)
|
Heat of vaporization
|
(d)
|
Freezing point
|
13. The
boiling point of liquid is …………… to external pressure.
|
(a)
|
Directly proportional
|
(b)
|
Inversely proportional
|
|
(c)
|
Independent
|
(d)
|
None of the above.
|
14. Cooking
takes ……………… time at high altitude mountains than plain area:
|
(a)
|
Longer
|
(b)
|
Shorter
|
|
(c)
|
Equal
|
(d)
|
None of the above.
|
15. At
higher altitude water boils at temperature:
|
(a)
|
Lower than 100°C
|
(b)
|
Higher than 100°C
|
|
(c)
|
100°C
|
(d)
|
None of the above.
|
16. At
Murree hills water boils at:
|
(a)
|
98°C
|
(b)
|
96°C
|
|
(c)
|
100°C
|
(d)
|
94°C
|
17. It
is based on the principle that boiling points are lowered at lower vapour
pressure:
|
(a)
|
Sublimation
|
(b)
|
Crystallization
|
|
(c)
|
Vacuum distillation
|
(d)
|
Evaporation
|
18. Vacuum
distillation is used to avoid:
|
(a)
|
Decomposition
|
(b)
|
Crystallization
|
|
(c)
|
Condensation
|
(d)
|
Evaporation
|
19. The process of heating the liquid under
reduced pressure to change it into vapours at a lower temperature and then condensing the
vapours to a liquid is called:
|
(a)
|
Vacuum distillation
|
(b)
|
Crystallization
|
|
(c)
|
Condensation
|
(d)
|
Evaporation
|
20. The
internal resistance to flow of a liquid which is due to internal friction is
called:
|
(a)
|
Fluidity
|
(b)
|
Crystallization
|
|
(c)
|
Vapour pressure
|
(d)
|
Viscosity
|
21. Which
one is more viscous?
|
(a)
|
H2O
|
(b)
|
CH3OH
|
|
(c)
|
CH3OCH3
|
(d)
|
C6H6
|
22. With
the rise in temperature, viscosity of liquids ……………….
|
(a)
|
Slightly increases
|
(b)
|
Decreases
|
|
(c)
|
Increases
|
(d)
|
Remain sam
|
23. Viscosity
of a liquid is measured by:
|
(a)
|
Stalagmometer
|
(b)
|
Ostwald’s meter
|
|
(c)
|
Hydrometer
|
(d)
|
Barometer
|
24. The
S.I. unit of viscosity is:
|
(a)
|
N-s-m–2
|
(b)
|
N-s-m2
|
|
(c)
|
N-s-m–1
|
(d)
|
None of the above
|
25. Which
one is correct relation?
|
(a)
|
1 centipoise = 10–3 N-s-m–2
|
(b)
|
1 centipoise = 10–3 N-s-m–2
|
|
(c)
|
1 centipoise = 10–3 N-s-m–2
|
(d)
|
None of the above
|
26. The amount of energy required to expand the
surface of a liquid by unit area is called:
|
(a)
|
Viscosity
|
(b)
|
Surface tension
|
|
(c)
|
Vapour pressure
|
(d)
|
None of the above
|
27. The force in dynes acting
perpendicularly on a unit length of the surface of the liquid is called
|
(a)
|
Viscosity
|
(b)
|
Surface tension
|
|
(c)
|
Vapour pressure
|
(d)
|
None of the above
|
28. The
unit of surface tension is:
|
(a)
|
N-m-1 or dyne-cm–1
|
(b)
|
J-m–2
|
|
(c)
|
Ergs-cm–2
|
(d)
|
All of the above
|
29. The
surface tension of a liquid …………….. with the rise in temperature of the liquid.
|
(a)
|
Slightly increases
|
(b)
|
Decreases
|
|
(c)
|
Increases
|
(d)
|
Remains same
|
30. The
forces of attraction among the particles of liquid are called:
|
(a)
|
Cohesive forces
|
(b)
|
Adhesive forces
|
|
(c)
|
Capillary action
|
(d)
|
All of the above
|
31. The
forces of attraction between a liquid molecules and another surface is called:
|
(a)
|
Cohesive forces
|
(b)
|
Adhesive forces
|
|
(c)
|
Capillary action
|
(d)
|
Hydrogen bonding
|
32. Surface
tension and viscosity are …….. dependent functions:
|
(a)
|
Volume
|
(b)
|
Pressure
|
|
(c)
|
Temperature
|
(d)
|
None of the above
|
33. Which
one of the following reduces the surface tension of water?
|
(a)
|
Honey
|
(b)
|
Na
|
|
(c)
|
Detergents
|
(d)
|
NaCl
|
34. Which
apparatus is used to measure surface tension?
|
(a)
|
Hypsometer
|
(b)
|
Ostwald’s meter
|
|
(c)
|
Stalagmometer
|
(d)
|
Barometer
|
35. Wetting
liquids form which type of meniscus?
|
(a)
|
Concave
|
(b)
|
Convex
|
|
(c)
|
None of the above
|
(d)
|
All of the above
|
36. Non-wetting
liquids form which type of meniscus?
|
(a)
|
Concave
|
(b)
|
Convex
|
|
(c)
|
None of the above
|
(d)
|
All of the above
|
37. Mercury
forms which type of meniscus?
|
(a)
|
Concave
|
(b)
|
Convex
|
|
(c)
|
None of the above
|
(d)
|
All of them
|
38. Water
forms which type of meniscus?
|
(a)
|
Concave
|
(b)
|
Convex
|
|
(c)
|
None of the above
|
(d)
|
All of the above
|
39. Adhesive
forces are stronger than the cohesive forces in:
|
(a)
|
Wetting liquids
|
(b)
|
Non-wetting liquid
|
|
(c)
|
None of the above
|
(d)
|
All of the above
|
40. Cohesive
forces are stronger than the adhesive forces in:
|
(a)
|
Wetting liquids
|
(b)
|
Non-wetting liquid
|
|
(c)
|
None of the above
|
(d)
|
All of the above
|
41. The
spontaneous rise of a liquid in a capillary tube is called:
|
(a)
|
Surface tension
|
(b)
|
Capillary action
|
|
(c)
|
Viscosity
|
(d)
|
None of the above
|
42. Capillary
action is due to:
|
(a)
|
Surface tension
|
(b)
|
Vapour pressure
|
|
(c)
|
Viscosity
|
(d)
|
All of the above
|
43. A
drop of ink or ink spreads on a blotting paper because of:
|
(a)
|
Surface tension
|
(b)
|
Capillary action
|
|
(c)
|
Viscosity
|
(d)
|
None of the above
|
44. A
falling drop of a liquid is always spherical due to:
|
(a)
|
Surface tension
|
(b)
|
Capillary action
|
|
(c)
|
Viscosity
|
(d)
|
None of the above
|
45. It is a measure of the strength of
intermolecular attractive forces holding the liquid molecules in a liquid state:
|
(a)
|
Boiling point
|
(b)
|
Density
|
|
(c)
|
Specific heat
|
(d)
|
None of the above
|
46. It
is a measure of average K.E. of the molecules of a liquid?
|
(a)
|
Temperature
|
(b)
|
Heat
|
|
(c)
|
Pressure
|
(d)
|
None of the above
|
47. Values
of heat of vapourization for liquids with strong dipole-dipole forces will be:
|
(a)
|
Negligible
|
(b)
|
Very low
|
|
(c)
|
Very high
|
(d)
|
Reasonably high
|
48. The
function of detergents is to:
|
(a)
|
Increase the surface tension of water.
|
|
(b)
|
Decrease the viscosity of water.
|
|
(c)
|
Increase the vapour pressure of water.
|
|
(d)
|
Reduce the surface tension of water.
|
49. Why
is a falling drop of a liquid spherical?
|
(a)
|
As in a sphere, ratio of surface to volume is smallest.
|
|
(b)
|
As in a sphere, ratio of surface to volume is largest.
|
|
(c)
|
As in a sphere, ratio of surface to volume is zero.
|
|
(d)
|
Reduce the surface tension of water.
|
50. Which
statement is correct regarding evaporation?
|
(a)
|
It is the spontaneous and continuous
escaping of a liquid from its surface into vapour phase.
|
|
(b)
|
It is a surface phenomenon and it occurs at all temperature.
|
|
(c)
|
It causes cooling.
|
|
(d)
|
All of the above.
|
51. Which
order is correct?
|
(a)
|
Hydrogen bonding > Dipole-dipole interaction > London forces
|
|
(b)
|
Dipole-dipole interaction > London forces > Hydrogen bonding
|
|
(c)
|
London forces > Hydrogen bonding > Dipole-dipole interaction
|
|
(d)
|
Hydrogen bonding > London forces > Dipole-dipole interaction
|
52. Which
statement is correct regarding vapour pressure?
|
(a)
|
It is the
pressure exerted by the vapours in equilibrium with its pure liquid at a
given temperature.
|
|
(b)
|
It is measured with the help of a mercury barometer.
|
|
(c)
|
It is an example of extensive property.
|
|
(d)
|
It is a measure of tendency of a liquid to evaporate.
|
No comments:
Post a Comment