Free Kinetic Molecular Theory MCQs with Answers
122 Kinetic Molecular Theory MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Kinetic molecular theory explains gases as rapidly moving particles separated by large distances, with negligible volume and negligible intermolecular attraction in the ideal model. It relates temperature to average kinetic energy and explains gas pressure, Boyle's and Charles's laws, diffusion, effusion and the conditions under which real gases deviate from ideal behavior.
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122 questions · page 2 of 7
- A. Unchanged
- B. Slightly decreased
- C. Slightly increased
- D. Zero
Explanation: According to the classical kinetic theory, gas diffusion depends on random molecular motion, and the average kinetic energy is…
Correct answer: Zero- A. Ne
- B. N2
- C. NH3
- D. CO
Explanation: At the same temperature and pressure, gas density is proportional to molar mass.
Correct answer: NH3- A. CO is 1.25 times faster than CO2
- B. CO is 3.75 times faster than CO2
- C. CO is 1.25 times faster than CO
- D. Both diffuse at the same rate
Explanation: By Graham's law, rate of effusion is inversely proportional to the square root of molar mass: rate of CO/rate of CO2 = square root of 44…
Correct answer: CO is 1.25 times faster than CO2- A. Fluorescent bulb
- B. Neon signs
- C. Lasers
- D. All of these
Explanation: Plasma is an ionised gas containing free electrons and positive ions, and it conducts electricity and emits light.
Correct answer: All of these- A. Average kinetic energy of molecules
- B. Vibrational kinetic energy
- C. Translational kinetic energy
- D. None of the above
Explanation: In a solid, particles cannot move freely from place to place; they vibrate about fixed positions.
Correct answer: Vibrational kinetic energy- A. 20cm3/min
- B. 40cm3/min
- C. 160cm3/min
- D. 2.5cm3/min
Explanation: Graham's law gives rate1/rate2 = √(M2/M1). Therefore, rate of hydrogen = 10 cm3/min x √(32/2) = 10 cm3/min x 4 = 40 cm3/min.
Correct answer: 40cm3/min- A. h 2,
- B. Nh3
- C. He
- D. oy
Explanation: as NH3 is sp3 hybridized so it is surrounded by 4 lobes (1 lonepair and other 3 bond pair) so which is why it only show transitional…
Correct answer: Nh3- A. no attraction and repulsion forces between molecules
- B. yom
- C. yo O poc- 1
- D. poc-
Explanation: as gas particle are far apart so inter molecular forces becomes less almost negligible
Correct answer: no attraction and repulsion forces between molecules- A. 1/3ρ<v^2>
- B. 3/2ρ(v^2)
- C. 1/3ρ(v)
- D. 1/3ρ(v^2)
Explanation: The pressure of a gas can be expressed using the kinetic theory of gases as (d) 1/3ρ(v^2), where P is the pressure, ρ is the density, and…
Correct answer: 1/3ρ(v^2)- A. 1.38 x 10^23 JK
- B. 1.38 x 10^-23 JK^-1
- C. 1.38 x 10^-23 JK
- D. 1.38 x 10^26 JK^-¹
Explanation: The pressure of a gas can be expressed using the kinetic theory of gases as (d) 1/3ρ(v^2), where P is the pressure, ρ is the density, and…
Correct answer: 1.38 x 10^-23 JK^-131. Which of the following gases possess the maximum root mean square velocity at a given temperature?
- A. Hydrogen
- B. Oxygen
- C. Nitrogen
- D. Options (b), (c), and (d) have higher molar masses compared to hydrogen, leading to lower root mean square velocities at the same temperature.
Explanation: The root mean square velocity of a gas is inversely proportional to the square root of its molar mass.
Correct answer: Hydrogen- A. The pressure exerted by a gas is proportional to mean squarevelocity of the molecules
- B. The pressure exerted by the gas is proportional to the rootmean square velocity of the molecules
- C. The root mean square velocity is inversely proportional to thetemperature
- D. The mean translational K.E. of the molecule is directlyproportional to the absolute temperature
Explanation: According to kinetic theory, the mean translational kinetic energy of a gas molecule is directly proportional to theabsolute temperature.
Correct answer: The mean translational K.E. of the molecule is directlyproportional to the absolute temperature- A. I only
- B. I, II and III
- C. III only
- D. I and II only
Explanation: All three postulates are foundational to the Kinetic Theory of Gases. They allow for a simplified mathematical model by treating gas…
Correct answer: I, II and III- A. The gas is at high pressure
- B. The collisions between particles are elastic
- C. There are weak forces of attraction between the particles in the gas
- D. The total energy of particles is proportional to the temperature
Explanation: OPTION A: The gas behave ideally at low pressure and at high temperature.OPTION B: According to KMT, all the collisions of a gas molecule…
Correct answer: The collisions between particles are elastic- 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