Free Gases MCQs with Answers

443 Gases MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.

Gas behaviour is explained through the kinetic molecular theory and the relationships among pressure, volume and temperature. Work includes STP, Boyle's and Charles's laws, absolute zero, the ideal gas equation, and the distinction between ideal and real gases, especially the effects of intermolecular forces and molecular volume.

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443 questions · page 17 of 23

  • A. Highly stable
  • B. Covalent Molecule
  • C. Highly reactive
  • D. Carbon molecule

Explanation: In CO2, carbon, and oxygen first form a double covalent bond. At first, oxygen and carbon share their two valence electrons.

Correct answer: Covalent Molecule
  • A. Easy to be liquified
  • B. Having higher critical temperature
  • C. Less soluble in water
  • D. None

Explanation: A gas having high value of coefficient of attraction is tough to be liquified.

Correct answer: Easy to be liquified
  • A. 2.71 A
  • B. 2.71 nm
  • C. 5.42 A0
  • D. 542 A0

Explanation: According to the following solution this correct answer is 2.71Ao.

Correct answer: 2.71 A
  • A. the constant 'a' is negligible and not 'b'
  • B. the constant 'b' is negligible and not 'a'
  • C. both constants 'a' & 'b' are negligible
  • D. both the constants 'a' & 'b' are not negligible

Explanation: At low pressure, b can be ignored as the volume of the gas is very high.

Correct answer: the constant 'a' is negligible and not 'b'
  • A. No force of attraction between molecules
  • B. No example in nature
  • C. Can be liquefied easily
  • D. Obey gas laws at all conditions of temperature and pressure

Explanation: Ideal gases cannot be liquefied easily. This is because ideal gases have no intermolecular forces, which are the forces that hold…

Correct answer: Can be liquefied easily
  • A. N2
  • B. CO2
  • C. NH3
  • D. SO2

Explanation: the non ideal behaviour of a gas depends on two factors: 1. intermolecular forces 2.

Correct answer: N2
  • A. Low temperature and low pressure
  • B. Standard temperature and standard pressure
  • C. Low temperature and high pressure
  • D. High temperature and low pressure

Explanation: Real gases behave most like ideal gases under conditions of high temperature and low pressure.When the temperature is high,the kinetic…

Correct answer: High temperature and low pressure
  • A. Its critical temperature is always above 0°C
  • B. Its molecules are smaller in size
  • C. It solidifies before becoming a liquid
  • D. Forces between its molecules are negligible

Explanation: An ideal gas cannot be liquefied because intermolecular forces are negligible.For a gas to be converted into a liquid state,it should have…

Correct answer: Forces between its molecules are negligible
  • A. Zero
  • B. Less than one
  • C. Greater than one
  • D. Equal to one

Explanation: For an ideal gas,the value of compressibility factor is one.While for real gas,it is greater or less than one.

Correct answer: Equal to one
  • A. Nm-4mol-2
  • B. Nm+6mol-2
  • C. Nm+4mol-2
  • D. Nm+2 mol-2

Explanation: Nm+2 mol-2 is the unit of gas constant a

Correct answer: Nm+4mol-2
  • A. The molecules of the gas are big sized
  • B. Gas is sufficiently polar.
  • C. Least attractive forces are present among the molecules of the gas
  • D. The gases are non-ideal

Explanation: Very small values of Van der Waal's constant in his equation for a particular gas show that least attractive forces are present among the…

Correct answer: Least attractive forces are present among the molecules of the gas
  • A. Two
  • B. Three
  • C. Four
  • D. Eight

Explanation: It is interesting to know that the excluded volume b is not equal to the actual volume of gas molecules.In fact,it is four times the…

Correct answer: Four
  • A. Helium
  • B. Hydrogen
  • C. Oxygen
  • D. Ammonia

Explanation: 'a' is coefficient of attraction or attraction per unit volume.Since ammonia has hydrogen bonding (strong intermolecular forces of…

Correct answer: Ammonia
  • A. Helium
  • B. Ammonia
  • C. Oxygen
  • D. CO2

Explanation: Correct. Ammonia has a high critical temperature of ~405.5 K because of strong hydrogen bonding between its molecules, which increases…

Correct answer: Ammonia
  • A. 3.5 atm
  • B. 1 atm
  • C. 3 atm
  • D. 1.25 atm
  • E. 2.25 atm

Explanation: 1 atm -> 760 torr X atm ->950 torr X=1.25 atm

Correct answer: 1.25 atm
  • A. 400 torr
  • B. 50662 Pa
  • C. 101.3 Pa
  • D. 8.5 pounds

Explanation: Atmospheric pressure on sea level is 101,325 Pa/760 torr/14.7 pounds per inch.

Correct answer: 50662 Pa
  • A. 1.050
  • B. 10.38
  • C. 1.380
  • D. 2.760

Explanation: The torr is a unit of pressure defined as exactly 1/760 of a standard atmosphere.

Correct answer: 1.380
  • A. 350 K
  • B. 343 K
  • C. 300 K
  • D. 283 K

Explanation: To convert temperature from celsius to kelvin scale the formula is °C + 273.15 K 70° + 273.15 =343 K.

Correct answer: 343 K
  • A. 754 torr
  • B. 54.6 mm of water
  • C. 1.01 atm
  • D. 74.0 cm Hg

Explanation: 1 inch of Hg = 2.54 cm of Hg 30.2 inches of Hg = 30.2 (2.54) cm of Hg = 30.2 (5.08/2) = 15.1(5.08) = 76.7 cm of Hg = 767 torr 760 torr = 1…

Correct answer: 1.01 atm
  • A. Nm-2
  • B. Nm2
  • C. mm of Hg
  • D. atm

Explanation: Pressure:Pressure is defined as force per unit area. P = F/ A---> P = N/m^2---> P = Nm^-2 Hence, A is the correct option.

Correct answer: Nm-2