ECAT Pre Engineering Chemistry Chapter 3 MCQ Test With Answer

Question # 1

Number of molecules in one dm³of water is close to :

6.02/22.4

A
12.04/22.4 *10²³

B
18/22.4*10²³
C
55.6*6.02*10²³* 10²³
D

Question # 2

The graph between pressure and volume at constant temperature for a gas is

Isobaric A
Isothermal B
Isotherm C
None of above D

Question # 3

Pressure remaining constant, at which temperature volume of gas will become twice of what it is at 0°C ?

546
A
200 B
546K C
273K D

Question # 4

In Boyle's law which of the following pair is variable

Temperature and quantity of a gas A
Pressure and Volume B
Volume and quantity of a gas C
Pressure and quantity of a gas D

Question # 5

Keeping the temperature constant, if the gas is expanded

kinetic energy of molecules will increase A
Number of gas molecules increases B
Temperature will increases C
Pressure will decrease D

Question # 6

In gases and liquids, temperature is the measure of :

Average transnational kinetic energies of molecules. A
Average vibrational kinetic energies of molecules. B
Average rotational kinetic energies of molecules. C
None of above D

Question # 7

How should condition be changed to prevent the volume of a given gas from expanding whine its mass is increased ?

Temperature is lowered and pressure is increased A
Temperature is increasedand pressure is lowered B
Temperature and pressure both are lowered C
Temperature and pressure both are increased D

Question # 8

In Boyle's law which of the following pair is variable :

Temperature and quantity of a gas. A
Pressure and volume B
Volume and quantity of a gas. C
Pressure and quantity of a gas. D

Question # 9

The movement of molecules from a region of high pressure to vacuum is called :

Evaporation A
Effusion B
Conduction C
Difusion D

Question # 10

All gases can be compressed by :

Keeping constant pressure A
Decreasing pressure B
Increasing pressure C
None of the above D

Question # 11

The order of the rate of diffusion of gases NH₃,SO₂, CL₂, and CO₂ IS :

NH_{3 >}SO_{2 >}CL_{2 >}CO₂ A
NH_{3 >}CO_{2 >}SO_{2 >}CL₂ B
CL_{2 >}SO_{2 >}CO_{2 >}NH₃ C
NH_{3 >}CO₂_>CL_{2 >}SO₂ D

Question # 12

Cooling happens under the Joule Thomson Effect due to sudden :

Contraction A
Absortption B
Expansion C
All of above D

Question # 13

Gases of air always remain in random motion and do not settle due to :

Difference in molecular masses of air gases. A
Difference in partial pressure of gas molecules. B
Unequal number of different gas molecules. C
Elastic collision of gas molecules. D

Question # 14

If absolute temperature of a gas is doubled and the pressure is reduced to one half, the volume of gas will :

remain unchanged A
increase four times B
reduce to 1/4 C
be doubled D

Question # 15

Liquids are less common than :

Solids A
Plasmas B
Gases C
All of above D

Question # 16

For a gas obeying Boyle's law if pressure is doubled, the volume becomes

Remains constant A
Double B
One half C
None of above D

Question # 17

A graph between P and PV at constant temperature and number of mole is parallel to

y axis A
z axis B
x axis C
pressure axis D

Question # 18

A graph b/w P and 1/V at constant temperature and number of moles is parallel to :

None of above A
X-axis B
Z-axis C
Y-axis D

Question # 19

Which statement about gases is not correct ?

The spread throughout the vessel. A
Pressure is due to collision B
There are large spaces between the molecules. C
molecules are arranged regularly. D

Question # 20

The highest temperature at which a substance can exist as a liquid is called its

Critical temperature A
Zero temperature B
Absolute temperature C
None of above D

Question # 21

A graph between P and 1/V at constant temperature and number moles of a gas meets the

y-axis A
x-axis B
origin C
none of above D

Question # 22

Gases shows uniform behavior toward their :

Internal conditions A
External conditions B
Internal and external conditions C
None of above D

Question # 23

The product of pressure and volume remains constant when temperature and quantity of gas is

zero A
variable B
kept constant C
None of these D

Question # 24

Which of the following is the simplest form of matter?

Gaseous state A
Liquid state B
Solid state C
All of above D

Question # 25

Which of the following will have the same number of molecules at STP ?

280 CM³ of CO² and 280 CM³ of N₂O
A
11.2 dm3 of O₂ and 32 g of O₂
B
44 g of CO₂ and 11.2 dm³ of CO
C
28 g of N2 and 5.6 dm³ of oxygen
D

Question # 26

The intramolecular force in gases are :

Weak A
Normal B
Very weak C
Strong D

Question # 27

In gases and liquids, temperature is the measure of

Average translational kinetic energies of molecules A
Average vibrational kinetic energies of molecules B
Average rotational kinetic energies of molecules C
None of above D

Question # 28

Equal masses of methane and oxygen are mixed in an empty container at 25°CThe fraction of total pressure exerted by oxygen is :

1/2 A
8/9 B
1/9 C
16/17 D

Question # 29

Boyle's law is represented as :

P∞ 1/T
A
V and 1/P B
P∞P C
P∞1/P D

Question # 30

A real gas obeying van der Waals' equation will resemble ideal gas if :

both 'a' and 'b' are large A
both 'a' and 'b' are small B
'a' is small and 'b' is large C
'a' is large and 'b' is small D

Sr.#	Question	Answer
1	The movement of gas molecules from a region of high pressure to vacuum is called	A. Evaportation B. Effusion C. Conduction D. Diffusion
2	Gases show uniform behaviour towards their	A. Internal conditions B. External conditions C. Internal and external conditions D. None of above
3	Gases shows uniform behavior toward their :	A. Internal conditions B. External conditions C. Internal and external conditions D. None of above
4	Boyle's law does not fall even	A. Temperature is extremely high B. Pressure is extremely high C. Mixture of gases is taken D. all of above
5	A graph between P and PV at constant temperature and number of mole is parallel to	A. y axis B. z axis C. x axis D. pressure axis
6	Cooling happens under the Joule Thomson Effect due to sudden	A. Contraction B. Absorption C. Expansion D. All of above
7	The product of pressure and volume remains constant when temperature and quantity of gas is	A. zero B. variable C. kept constant D. None of these
8	Liquids are less common than :	A. Solids B. Plasmas C. Gases D. All of above
9	A real gas obeying van der Waals' equation will resemble ideal gas if :	A. both 'a' and 'b' are large B. both 'a' and 'b' are small C. 'a' is small and 'b' is large D. 'a' is large and 'b' is small
10	Pressure remaining constant, at which temperature volume of gas will become twice of what it is at 0°C ?	A. 546 B. 200 C. 546K D. 273K

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