ECAT Pre Engineering Chemistry Chapter 4 MCQ Test With Answer

Question # 1

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 # 2

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

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

Question # 3

A liquid on evaporation causes:

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

Question # 4

Force of attraction between atoms of He is

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

Question # 5

The density of water decreases, When it is freezed at 0°C

Change of bond length A
Change of bond angles B
Cubic structure of ice C
Empty spaces present in the structure of ice D

Question # 6

Hydrocarbon molecules with large chain lengths experience

Weaker attractive forces A
Stronger attractive forces B
Repulsive forces C
No attractive forces D

Question # 7

The gases can be converted into liquids by

increasing the pressure only A
Lowering temperature and increasing pressure B
Increasing pressure and bringing temperature below critical point C
Lowering temperature only D

Question # 8

The molecules of CO_{2 in dry ice from the :}

Ionic crystals A
Coverlet crystals B
Molecular crystals C
Any type of crystals D

Question # 9

Force of attraction b/w atoms of He is :

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

Question # 10

Chloroform and acetone are soluble in each other due to

Instantaneous dipole interactions A
Dipole-dipole interactions B
Intermolecular hydrogen bonding C
All of above D

Question # 11

]Which of the following is a pseudo solid?

Atoms of He is gaseous stat at high temperate. A
Molecules of water in liquid state. B
Molecules of solid l₂ C
Molecular of hydrochloric acid gas D

Question # 12

The molecules of CO₂in dry ice from the

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

Question # 13

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 # 14

Chloroform and acetone are soluble in each other due to:

Instantaneous dipole interactions. A
Dipole-dipole interactions. B
Inter molecular hydrogen bonding. C
All of above D

Question # 15

London dispersion forces are alos called:

Hydrogen bonding. A
Debye forces B
Van der Waal's forces C
Instantaneous dipole-induced dipole forces. D

Question # 16

Which of the following is a pseudo solid?

CaF₂
A
Glass
B
NaCL
C
All
D

Question # 17

H₂S is a gas which H₂O is liquid at room temperature. it is due to

Less intermolecular forces in water A
Covalent bond in H-O in water molecule B
Hydrogen bonding in water molecules C
Ionic characters in water molecules D

Question # 18

The inter-molecular forces in liquids are:

Negligible A
Very weak B
Very strong C
Reasonably strong D

Question # 19

Hydrogen bonding is present in one of the following pairs:

NH₃ A
H₂O B
HF C
All of above 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

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 # 22

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 # 23

Trend of boiling point of halogens from fluorine to Iodine is that it

Decreases A
Is negligible B
Increases C
Remains constant D

Question # 24

In a group on going downward, polarizability generally:

Decreases A
Increases B
Remain constant C
Negligible D

Question # 25

Evaporation of water is possible at:

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

Question # 26

Which one of the following is weakest inter molecular force?

Dipole induced dipole forces A
Ionic dipole forces B
Electrostatic forces b/w ions C
Dipole dipole forces D

Question # 27

A liquid on evaporation causes

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

Question # 28

HF has exceptionally low acidic strengths due to

Smaller size of fluorine A
Strong polar bond between H and F B
Electronegativity of fluorine C
Strong hydrogen bonding D

Question # 29

The strongest forces are:

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

Question # 30

Hydrocarbon molecule with large chain lengths experience:

Weaker attractive forces A
Stronger attractive forces B
Repulsive forces C
No attractive forces D

Sr.#	Question	Answer
1	Which of the following is a pseudo solid	A. CaF₂ B. Glass C. NaCl D. All
2	Debye forces are present in on of the following pairs:	A. Na+ion and water B. Argon and water C. Argon and Na+ion D. Ne and water
3	Chloroform and acetone are soluble in each other due to:	A. Instantaneous dipole interactions. B. Dipole-dipole interactions. C. Inter molecular hydrogen bonding. D. All of above
4	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
5	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
6	Heat of vapourization for liquids with strong dipole-dipole forces will have	A. Negligible Values B. Reasonably high values C. Very high values D. very low values
7	The molecules of CO₂in dry ice from the	A. Ionic crystalls B. Covalent crystals C. Molecular crystals D. Any type of crystal
8	Chloroform and acetone are soluble in each other due to	A. Instantaneous dipole interactions B. Dipole-dipole interactions C. Intermolecular hydrogen bonding D. All of above
9	In a group on going downward, polarizability generally	A. Decreases B. Increases C. Remains constant D. Negligible
10	The strongest forces are	A. Debye forces B. London dispersion forces C. Dipole-dipole attraction D. Hydrogen

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