ECAT Pre Engineering Chemistry Chapter 3 MCQ Test With Answer

Question # 1

Boyle's law is represented as :

P∞ 1/T
A
V and 1/P B
P∞P C
P∞1/P D

Question # 2

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 # 3

In Boyle's law which of the following pair remains constant :

Temperature and quality of a gas. A
Pressure and quality of a gas. B
Temperature and pressure C
Temperature and quantity of a gas. D

Question # 4

Gases exert pressure on walls of container because the gas molecules :

Obey gas laws. A
Have definite volume. B
Collide with the walls of container. C
Collide with each other. D

Question # 5

Cooling happens under the Joule Thomson Effect due to sudden

Contraction A
Absorption B
Expansion C
All of above D

Question # 6

According to Boyle's law, which parameters give a straight line parallel to axis-s, when we plot a graph between:

V and T A
P and V B
P and 1/V C
P and PV D

Question # 7

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

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

Question # 8

The ratio of volume to temperature on Kelvin scale is constant according to

Charle's law A
Newton's law B
Coulomb's law C
Boyle's law D

Question # 9

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 # 10

According to Boyle's law. which parameters give a straight line parallel to x-axis, when we plot a graph between

V and T A
P and V B
P and 1/V C
P and PV D

Question # 11

Liquids are less common than :

Solids A
Plasmas B
Gases C
All of above D

Question # 12

All gases can be compressed by

Keeping constant pressure A
Decreasing pressure B
Increasing pressure C
None 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

The density of a gas is directly and volume at constant temperature for a gas is

Isobaric A
Isothermal B
Isotherm C
None of above D

Question # 15

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 # 16

The intramolecular force in gases are :

Weak A
Normal B
Very weak C
Strong D

Question # 17

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 # 18

In Solids, the temperature is the measure of

Rotational kinetic energies A
Translational kinetic energies B
Vibrational kinetic energies C
None of above 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 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 # 21

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 # 22

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

Evaportation A
Effusion B
Conduction C
Diffusion D

Question # 23

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

Question # 24

All gases can be compressed by :

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

Question # 25

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

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

Question # 26

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 # 27

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 # 28

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 # 29

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 # 30

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

Sr.#	Question	Answer
1	In Boyle's law which of the following pair is variable	A. Temperature and quantity of a gas B. Pressure and Volume C. Volume and quantity of a gas D. Pressure and quantity of a gas
2	The density of a gas is directly and volume at constant temperature for a gas is	A. Isobaric B. Isothermal C. Isotherm D. None of above
3	Cooling happens under the Joule Thomson Effect due to sudden :	A. Contraction B. Absortption C. Expansion D. All of above
4	Which of the following will have the same number of molecules at STP ?	A. 280 CM³ of CO² and 280 CM³ of N₂O B. 11.2 dm3 of O₂ and 32 g of O₂ C. 44 g of CO₂ and 11.2 dm³ of CO D. 28 g of N2 and 5.6 dm³ of oxygen
5	The relationships between volume of a given amount of gas and the prevailing conditions of temperature and pressure are	A. Charle's Law B. Graham's Law C. Boyle's Law D. Gas Laws
6	Number of molecules in one dm³of water is close to :	A. 6.02/22.4 B. 12.04/22.4 10²³ C. 18/22.410²³ D. 55.66.0210²³* 10²³
7	Gases exert pressure on walls of container because the gas molecules	A. Obey gas laws B. Have definite volume C. Collide with the walls of container D. Collide with each other
8	All gases can be compressed by	A. Keeping constant pressure B. Decreasing pressure C. Increasing pressure D. None of above
9	Gases of air always remain in random motion and do not settle due to :	A. Difference in molecular masses of air gases. B. Difference in partial pressure of gas molecules. C. Unequal number of different gas molecules. D. Elastic collision of gas molecules.
10	Boyle's law doesn't fail even :	A. Temperature is extremely high B. Pressure is extremely high C. Mixture of gas is taken D. All of above

Latest Educational News Stories

Pakistan's Largest Database of Colleges and Universities

BS Programs

University Past Papers

University Results

Exam Results 2024

Study Abroad Programs and Opportunities for Pakistani Students