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.
Last updated
443 questions · page 13 of 23
- A. Collisions between molecules and walls of container are elastic
- B. The duration of collision between molecules is very short
- C. All particles of gas has same speed
- D. All particles of gas have same mass
Explanation: In the kinetic model of an ideal gas, the assumption is that gas molecules are in constant random motion, colliding with each other and…
Correct answer: All particles of gas has same speed- A. I only
- B. II only
- C. III only
- D. I & II only
- E. I, II & III
Explanation: All the above-mentioned postulates refer to the kinetic theory of gases.
Correct answer: I, II & III- A. 14/3 m2/s2
- B. 6 m2/s2
- C. 2 m2/s2
- D. √(14/3) m/s
Explanation: To find the mean square speed of the gas sample, we need to calculate the average of the squares of the individual speeds.
Correct answer: 14/3 m2/s2- A. No change in the total kinetic energy
- B. The velocity of the molecules changes
- C. No change in potential energy during the collisions
- D. No change in mass during the collisions
Explanation: By definition, an 'Elastic collision' describes a collision whereby the total kinetic energy of the molecules is unchanged so, option A is…
Correct answer: No change in the total kinetic energy- A. 4
- B. 16
- C. 32
- D. 0.5
Explanation: Graham's law states that the rate of effusion or diffusion of a gas is inversely proportional to the square root of its molecular weight.
Correct answer: 4- A. 8
- B. 2
- C. 4
- D. 16
- E. 64
Explanation: Lets M1 be the mass of SO2 and M2 the mass of He. √M1/M2 = √64/4 = √16 = 4
Correct answer: 4- A. I ONLY
- B. II ONLY
- C. I AND II ONLY
- D. II AND III ONLY
- E. I, II, III
Explanation: According to Kinetic Molecular Theory , there are no attractive forces between the molecules of a gas because the distance between them is…
Correct answer: I, II, III- A. CO2 and N2O
- B. CO2 and CO
- C. NO2 and CO2
- D. CO2 and N2O4
Explanation: According to Graham's Law, the rate of diffusion or effusion is inversely proportional to the square root of molar mass.
Correct answer: CO2 and N2O- A. Size of pinhole
- B. Pressure
- C. Temperature
- D. Molecular mass
- E. All of the above
Explanation: Effusion: When gas is confined to a container at higher pressure than in the surrounding atmosphere it will escape from a small hole that…
Correct answer: All of the above- A. Hole dimensions
- B. Infinite dimensions
- C. Slit like dimensions
- D. Molecular dimensions
Explanation: Effusion moves the gas molecules from one container to another through a tiny hole however only a single molecule of gas passes thus it is…
Correct answer: Molecular dimensions- A. 6 times
- B. 4 times
- C. one fourth
- D. one eighth
Explanation: Graham's law states that the rate of effusion or of diffusion of a gas is inversely proportional to the square root of its molecular…
Correct answer: 4 times- A. Their mean square speed decreases
- B. Number of collision between molecules and walls of container decreased
- C. The force of attraction between them increase
- D. Their size decreases
Explanation: Pressure is proportional to temperature if the number of particles and the volume of the container is constant.
Correct answer: Number of collision between molecules and walls of container decreased- A. Indefinite volume
- B. Indefinite shape
- C. Low density
- D. Strong interactions
Explanation: Strong interactions as gases have weak interactions since the particles move quickly in random motion and move far apart from each other…
Correct answer: Strong interactions- A. Lower
- B. Higher
- C. Equal to
- D. All of these options are correct
Explanation: Diffusion is the intermixing (movement) of molecules. When looking at diffusion you must look at two factors: forces of attraction and…
Correct answer: Lower- A. Liquids
- B. Solids
- C. Plasma
- D. Gases
Explanation: Solids have the highest density as they have the most molecules per cubic volume.
Correct answer: Solids- A. None of these
- B. Solids
- C. Gases
- D. Liquids
Explanation: Density is defined as the mass per unit volume of a substance. Solids have tightly packed particles, which means greater mass per unit…
Correct answer: Gases- A. Plasma
- B. Liquids
- C. Solids
- D. Gases
Explanation: Plasma has the weakest intermolecular forces since its particles are far apart.
Correct answer: Plasma- A. Plasma
- B. Gases
- C. Solids
- D. Liquids
Explanation: Solids have the strongest intermolecular forces out of these because their molecules are closely packed as possess vibrational energies…
Correct answer: Solids- A. All statements are correct
- B. Only (b) and (c)
- C. Only (a), (b) and (c)
- D. Only (a) and (b)
Explanation: According to the Kinetic Molecular Theory of gases, gas molecules are in constant random motion and exhibit elastic collisions.
Correct answer: All statements are correct- A. Atomic theory
- B. Potential molecular theory
- C. Kinetic molecular theory
- D. None of these
Explanation: Option A: Atomic theory explains the behavior and properties of matter in terms of discrete, indivisible units called atoms.
Correct answer: Kinetic molecular theory