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 9 of 23
- A. PV = nRT
- B. PV = RT
- C. P1 V1 / T1 = P2 V2 / T2
- D. All of these
Explanation: The general gas equation, or combined gas law, relates the pressure, volume, and temperature of a fixed amount of gas.
Correct answer: PV = nRT- A. 3°C
- B. 819°C
- C. 819K
- D. 3K
Explanation: Using Charles's Law (V₁/T₁ = V₂/T₂), with T₁ being STP (273 K). T₂ = T₁(V₂/V₁) = 273 K × (30 dm³ / 10 dm³) = 273 × 3 = 819 K.
Correct answer: 819K- A. 44g CO2 and 44g CO
- B. 16g O2 and 32g CH4
- C. 3.01 x 10^23 molecules of CO and 3.01 x 10^23 gram molecules of H2
- D. 0.5 mole of NO and 16 g O2
Explanation: According to Avogadro's Law, equal moles of gases at the same temperature and pressure occupy equal volumes. 16 g of O₂ is 0.5 moles.
Correct answer: 0.5 mole of NO and 16 g O2- A. No force of attraction between molecules
- B. No example in nature
- C. Can be liquefied easily
- D. Obeys gas laws at all temperatures and pressures
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. Doubled
- B. Four times
- C. 300 times
- D. 327 times
Explanation: The average kinetic energy of a gas is directly proportional to its absolute temperature (in Kelvin).
Correct answer: Doubled- A. 8.314 atm dm3 mol-1 K-1
- B. 0.0821 J mol-1 K-1
- C. 62.4 torr cm3 mol-1 K-1
- D. 8.314 x 10^7 erg mol-1 K-1
Explanation: The value of the gas constant R depends on the units used. The value 8.314 x 10⁷ erg·mol⁻¹·K⁻¹ is a correct, though less common…
Correct answer: 8.314 x 10^7 erg mol-1 K-1- A. Average translational
- B. Rotational
- C. Vibrational
- D. All of these
Explanation: Temperature is a measure of the average kinetic energy of the particles in a system.
Correct answer: Average translational- A. 25°C and 1 atm
- B. 0°C and 2 atm
- C. 130°C and 1 atm
- D. 100°C and 2 atm
Explanation: According to the ideal gas law (V = nRT/P), molar volume (V/n) is directly proportional to temperature (T) and inversely proportional to…
Correct answer: 130°C and 1 atm- A. At high pressure,the gas molecules move in one direction only
- B. At high pressure,the collisions between the gas molecules are increased manifold
- C. At high pressure, the volume of the gas becomes insignificant
- D. At high pressure, the inter-molecular attractions become significant
Explanation: At high pressure, gas molecules are crowded, so their finite size and intermolecular attractions cause deviation from ideal behavior.
Correct answer: At high pressure, the inter-molecular attractions become significant- A. N2
- B. CO2
- C. NH3
- D. SO2
Explanation: Gases behave ideally when intermolecular forces are small. N₂ is non-polar with very weak London forces → behaves most ideally.
Correct answer: N2- A. Force
- B. Entropy
- C. Work
- D. Enthalpy
Explanation: The product of pressure and volume (PV) of a gas represents work, which is measured in joules (J).
Correct answer: Work- A. was
- B. were
- C. are
- D. have been
Explanation: In this sentence, the main subject is "The strain", which is a singular noun.
Correct answer: was- A. to
- B. Michele and me
- C. ourselves
- D. had
Explanation: "ourselves" is incorrect as it is a reflexive pronoun and is not required in this context. The correct pronoun should be "us."
Correct answer: ourselves- A. Over the rocky levels
- B. Of the mountain
- C. Rust coloured
- D. Air
Explanation: This is the problematic part. When used as a compound adjective to describe "air," it should be hyphenated as "rust-colored." This ensures…
Correct answer: Rust coloured- A. Avoid
- B. Provoke
- C. Solace
- D. Support
Explanation: Confront is to approach someone face to face, or stand up to them. Provoke is to elicit a reaction or draw forth someone (by confronting…
Correct answer: Provoke- A. Only conclusion I follows
- B. Only conclusion II follows
- C. Either I or II follows
- D. Neither I nor II follows
Explanation: The statement directly links a natural gift (good voice) with the need for practice (nurturing) to excel.
Correct answer: Only conclusion I follows- A. 41
- B. 44
- C. 23
- D. 21
Explanation: The difference between consecutive terms increases by 4 each time. The differences are +4, +8, +12. The next difference will be +16.
Correct answer: 41- A. True
- B. False
- C. Uncertain
- D. None of these
Explanation: If Joe is younger than Kathy, then Kathy is older than Joe. If Mark was born after Joe, then Mark is also younger than Joe.
Correct answer: True- A. Statement I is the cause and statement II is its effect
- B. Statement II is the cause and statement I is its effect
- C. Both the statements I and II are independent causes
- D. Both the statements I and II are effects of independent causes
Explanation: The petition and complaints from the teachers (Statement II) provided the reason and impetus for the university authorities to take…
Correct answer: Statement II is the cause and statement I is its effect- A. Only I follows
- B. Only II follows
- C. Either I or II follows
- D. Both I and II follow
Explanation: The statement explicitly identifies two problems: a need for flexibility and an outdated curriculum.
Correct answer: Both I and II follow