ECAT Pre Engineering Chemistry Chapter 4 MCQ Test With Answer

Question # 1

Which of the following liquids has low vapor pressure at 25°C:

Diethyl ether A
Acetone. B
Water. C
Ethyl alcohol. D

Question # 2

Rate of evaporation and rate of condensation at equilibrium:

Become very low A
Become very high B
Become equal C
Can never be equal. D

Question # 3

Heat of vapourization for liquids with strong dipole-dipole forces will have

Negligible Values A
Reasonably high values B
Very high values C
very low values D

Question # 4

Evaporation of water is possible at:

Above 100°C A
0°C B
100°C C
At all temperature D

Question # 5

Ionic solids are characterized by :

Low meeting points A
Good conductivity in solid state B
High vapor pressure C
Solubility in polar solvents D

Question # 6

Diamond is a bad conductor because:

Ithas tight structure A
It has a high density B
There is no free electron present in the crystal of diamond of conduct electricity is transparent to light C

Question # 7

In a group on going downward, polarizability generally:

Decreases A
Increases B
Remain constant C
Negligible D

Question # 8

The inter-molecular forces in liquids are:

Negligible A
Very weak B
Very strong C
Reasonably strong D

Question # 9

Diamond is a bad conductor because

It has a tight structure A
It has a high density B
there is no free electron present in the crystal of diamond of conduct electicity C
Is transparent to light D

Question # 10

At sea level and at 100⁰C the vapour pressure of water in an open system is

1000 mm Hg A
760 mm Hg B
730 mm Hg C
670 mm Hg D

Question # 11

Polypeptide chains are coiled about one another into a spiral by

Ionic bonds A
Covalent bonds B
Van der Waal's forces C
Hydrogen bonds D

Question # 12

A liquid on evaporation causes

Heating effect A
Cooling effect B
Suffication C
All of above D

Question # 13

Rate of evaporation and rate of condensation at equilibrium

Become very low A
Become very high B
Become equal C
Can never be equal D

Question # 14

Evaporation of water is possible at

Above 100⁰ A
0⁰ B
100⁰ C
At all temperature D

Question # 15

Which one of the following is the weakest intermolecular force

Dipole induced dipole forces A
Ionic dipole forces B
Electrostatics forces between ions C
Dipole-dipole forces D

Question # 16

Which of the following is a pseudo solid?

CaF₂
A
Glass
B
NaCL
C
All
D

Question # 17

Escape of high energy molecules from the surface of liquid is called:

Sublimation. A
Distillation. B
Condensation. C
Evaporation. D

Question # 18

Debye forces are present in one of the following pairs

Na⁺ion and water A
Argon and water B
Argon and Na⁺ion C
Ne and Water D

Question # 19

Debye forces are present in on of the following pairs:

Na+ion and water A
Argon and water B
Argon and Na+ion C
Ne and water D

Question # 20

Escape of high energy molecules from the surface of a liquid is called

Sublimation A
Distillation B
Condensation C
Evaporation D

Question # 21

The molecules of CO₂in dry ice from the

Ionic crystalls A
Covalent crystals B
Molecular crystals C
Any type of crystal D

Question # 22

At sea level and at 100°C the vapor pressure of water in an open system is:

1000 mm Hg A
760 mm Hg B
730 mm Hg C
670 mm Hg D

Question # 23

The only forces are London dispersion forces among the

Atoms of He in gaseous state at high temperature A
Molecules of water in liquid state B
Molecules of solid I₂ C
Molecular of hydrochloric acid gas D

Question # 24

The intermolecular forces in liquids are

Negligible A
Very weak B
Very strong C
Reasonably strong D

Question # 25

Which of the following liquids has low vapour pressure at 25°C:

Diethyl ether A
Acetone. B
Water. C
Ethyl alcohol. D

Question # 26

A liquid on evaporation causes:

Heating effect. A
Cooling effect. B
Suffocation . C
All of above D

Question # 27

Force of attraction between atoms of He is

London dispersion forces A
Hydrogen bondign B
Coordinate covalent bond C
Covalent bond D

Question # 28

Amorphous solids

Have sharp melting point A
Undergo clean cleavage when cut with knife B
Have perfect arrangement of atoms C
Can possesses small regions of orderly arrangement of atoms D

Question # 29

The strongest forces are:

Debye froces A
London dispersion B
Dipole-dipole attraction C
Hydrogen bonding D

Question # 30

The strongest forces are

Debye forces A
London dispersion forces B
Dipole-dipole attraction C
Hydrogen D

Sr.#	Question	Answer
1	A liquid on evaporation causes:	A. Heating effect. B. Cooling effect. C. Suffocation . D. All of above
2	Amorphous solids:	A. Have a sharp melting point B. Undergo clean cleavage when cut with knife C. Have a perfect arrangement of atoms D. Can possesses small regions of orderly arrangement of atoms
3	At sea level and at 100°C the vapor pressure of water in an open system is:	A. 1000 mm Hg B. 760 mm Hg C. 730 mm Hg D. 670 mm Hg
4	HF has exceptionally low acidic strengths due to	A. Smaller size of fluorine B. Strong polar bond between H and F C. Electronegativity of fluorine D. Strong hydrogen bonding
5	The only forces are London dispersion forces among the	A. Atoms of He in gaseous state at high temperature B. Molecules of water in liquid state C. Molecules of solid I₂ D. Molecular of hydrochloric acid gas
6	Which of the following liquids has low vapour pressure at 25⁰C	A. Diethyl ether B. Acetone C. Water D. Ethyl alochol
7	The boiling point of NH_{3 is maximum among the hydrides of group V elementsdue to:}	A. Enhanced electronegative character of Nitrogen B. Pyramidal structure of NH3 C. Very small size of Nitrogen. D. Enhanced electropositive character of Nitrogen
8	In a group on going downward, polarizability generally	A. Decreases B. Increases C. Remains constant D. Negligible
9	Which of the following liquids has low vapor pressure at 25°C:	A. Diethyl ether B. Acetone. C. Water. D. Ethyl alcohol.
10	The intermolecular forces in liquids are	A. Negligible B. Very weak C. Very strong D. Reasonably strong

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