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 12 of 23
- A. 2186.4 kg
- B. 2896.6 kg
- C. 2129.6 kg
- D. 2211.4 kg
Explanation: Total mass of the balloon= 25kg + 342.6 kg =367.6 kg Payload is the carrying capacity, Thus, Pay load = Mass of displaced air - Total mass…
Correct answer: 2186.4 kg- A. High temperature and low pressure
- B. Low temperature and high pressure
- C. Low temperature and pressure
- D. When temperature and pressure are same
Explanation: As we know, d = PM/RT Which shows that density is directly proportional to pressure and inveresely propotional to temperature.
Correct answer: Low temperature and high pressure- A. Straight line parallel to x-axis
- B. Straight line parallel to y-axis
- C. Straight line passing through the origin
- D. The curve showing the maximum
Explanation: A graph between pressure and the product of pressure and volume at constant temperature and number of moles is a straight line parallel to…
Correct answer: Straight line parallel to x-axis- A. Cannot be predicted
- B. Remain unchanged
- C. Is reduced to 1⁄2
- D. Is doubled
Explanation: If both temperature and volume of a gas are doubled, the pressure will remain the same.
Correct answer: Remain unchanged- A. 11.2 dm3
- B. 22.4 dm3
- C. 33.6 dm3
- D. 44.8 dm3
Explanation: 273K=0°C is the standard temperature. Moles of methane=mass/mr=8/(12+4)=0.5mol Volume=molxVolume at STP=0.5x22.4=11.2dm3 Moles of…
Correct answer: 33.6 dm3- A. Energy
- B. Force
- C. Energy per unit volume
- D. Force per unit volume
Explanation: The correct option is C as pressure and Energy per unit volume have the same dimensions that are ML-1T-2
Correct answer: Energy per unit volume- A. 1.989
- B. 8.314
- C. 0.0821
- D. 62400
Explanation: At STP, following are values of R in different units 0.0821 atm dm3 K-1 mol -1 8.31 Nm K-1 mol-1 8.31 J K-1 mol-1 7.989 cal K-1 mol-1
Correct answer: 0.0821- A. Units of pressure
- B. Units of volume
- C. Units of Temperature
- D. All of the above
Explanation: It is a constant and does not depend on other factors like temperature,pressure and volume.
Correct answer: All of the above- A. Remains same
- B. Becomes double
- C. Becomes half
- D. increases four times
Explanation: volume of a given amount of gas is directly proportional to the change in temperature (charles law)and inversely proportional to the…
Correct answer: Remains same- A. Increased four times
- B. Decreased four times
- C. Remained unchanged
- D. Reduced to one half
- E. Increased two times
Explanation: PV=nRT V=nRT/P If temperature is halved and pressure is doubled then V=n x R x 0.5T/2P = V=¼(nRT/P) Hence, volume is decreased four times.
Correct answer: Decreased four times- A. 1 atm, 0°C
- B. 2 atm, 10°C
- C. 3 atm, 546K
- D. All same
Explanation: Gas density is affected by both pressure and temperature according to the ideal gas law, PV = nRT.
Correct answer: 2 atm, 10°C- A. 8.3143 JK⁻¹mol⁻¹
- B. 0.0821 dm³atom mol⁻¹K⁻¹
- C. 8.3143 Jmol⁻¹
- D. 0.0821 dm³tor K⁻¹mol⁻¹
Explanation: The SI unit of R (the ideal gas constant) in the General Gas equation (PV = nRT) is 8.3143 J K⁻¹ mol⁻¹ (Joules per Kelvin per mole).
Correct answer: 8.3143 JK⁻¹mol⁻¹- 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^-1237. 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