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 21 of 23
- A. 30
- B. 99
- C. 50
- D. 80
Explanation: Explanation:The plasma is in four states of matter. It consists of neutral particles, positive ions, and negative electrons.
Correct answer: 99- A. Molar mass
- B. Temperature
- C. Pressure
- D. Volume
Explanation: A is correct as r.m.s velocity of gases is inversely proportional to the square root of their molar masses.B is incorrect as r.m.s…
Correct answer: Molar mass- A. Ions and electrons
- B. Electrons and neutral atoms
- C. Electrons, ions and neutral atoms
- D. Ions and neutral atoms
Explanation: A is incorrect as plasma is composed of ions,electrons and neutrals atoms.B is incorrect as plasma is composed of ions,electrons and…
Correct answer: Electrons, ions and neutral atoms- A. Neon
- B. Nitrogen
- C. Oxygen
- D. Fluorine
Explanation: Molar Mass: Approximately 20.18 g/mol.Density: Neon is a noble gas with a low molar mass, resulting in a low density compared to the other…
Correct answer: Neon- A. Solid.
- B. Liquid.
- C. Gas
- D. Isotope
Explanation: In thermodynamics, in the PV diagram, if liquid and vapor are present in equilibrium at a point, we call it a critical point.
Correct answer: Liquid.406. At a given temperature and pressure, the one which shows marked deviation from ideal behavior is
- A. N2
- B. N3
- C. CO2
- D. He
Explanation: The gas with higher intermolecular forces has the most marked deviation, as one of the assumptions of an ideal gas is that ideal gases…
Correct answer: CO2- A. Strong
- B. Moderate
- C. Weak
- D. Absent
Explanation: In an ideal gas, it is assumed that the intermolecular forces between gas molecules are absent.
Correct answer: Absent- A. Low temperature and low pressure
- B. High temperature and high pressure
- C. Low temperature and high pressure
- D. High temperature and low pressure
Explanation: Deviation from ideal gas behavior occurs primarily under high pressure and low temperature conditions.
Correct answer: Low temperature and high pressure- A. 20.414 dm3
- B. 22.414 dm3
- C. 22.414 cm3
- D. 23.414 dm3
Explanation: A is incorrect as the given volume is not correct under standard conditions.B is correct as the given volume (22.4 dm3) is correct under…
Correct answer: 22.414 dm3- A. 22.41 dm3
- B. 44.82 dm3
- C. 64.82 dm3
- D. 2.241 dm3
Explanation: To find the volume of a gas, we use the formula: Moles = Volume of gas / 22.
Correct answer: 22.41 dm3- A. N2
- B. H2
- C. O2
- D. Number of molecules are equal
Explanation: The number of molecules is given by the formula:Number of molceules = moles x avogadros constantSince all of the given elements have the…
Correct answer: Number of molecules are equal- A. Only translational motion
- B. Only vibrational motion
- C. Only rotational motion
- D. All motion is ceased
Explanation: At absolute zero, which is 0 Kelvin or -273.15°C, all molecular motion ceases.
Correct answer: All motion is ceased- A. Kept constant
- B. Zero
- C. Variable
- D. None of the above
Explanation: Its is kept constant. Imagine you have a balloon filled with gas. If you keep the temperature and the amount of gas inside the balloon…
Correct answer: Kept constant- A. 1/2
- B. 2x
- C. 4x
- D. 1/4
Explanation: Option B is correct. When the pressure of an ideal gas is reduced to half at a constant temperature, the volume of the gas will double.
Correct answer: 2x- A. Daltons Law
- B. Boyle's Law
- C. Avogadro's Law
- D. Charles law
Explanation: Charles' Law states that, at constant pressure, the volume of a fixed mass of gas is directly proportional to the absolute temperature.
Correct answer: Charles law416. A mixture of 50gH2 and 50gHe has a total pressure of 1.5atm. What is the partial pressure of H2 gas?
- A. 1.0 atm
- B. 2.0 atm
- C. 1.5 atm
- D. 3.0 atm
Explanation: Partial Pressure = Mole Fraction x Total Pressure Find moles of hydrogen and helium; moles = mass/Mr; moles = 50/2 = 25 moles of hydrogen…
Correct answer: 1.0 atm- A. 1.0atm
- B. 2.0atm
- C. 1.5atm
- D. 3.0atm
Explanation: Find moles of hydrogen and helium; moles = mass/Mr; moles = 50/2 = 25 moles of hydrogen moles= 50/4 = 12.5 moles of helium Total moles =…
Correct answer: 1.0atm418. If the pressure and temperature (k) of two liters of CO2 are doubled the volume of CO2 would become:
- A. 5 liters
- B. 4 liters
- C. 8 liters
- D. 2 liters
Explanation: As PV=nRT or V =nRT/PUsing P'=2P and T'=2T, we getV'= 2nRT/2PV'= nRT/PV'= VSo , the volume will be 2 litres.
Correct answer: 2 liters- A. The number of molecules in the gas
- B. Avogadro's number
- C. The number of kilo-moles
- D. The number of molecules per unit volume
Explanation: The ideal gas law can be written in terms of the number of molecules of gas: PV = nRT, where P is pressure, V is volume, T is temperature…
Correct answer: The number of molecules in the gas- A. (298)(750)(50)/(40)(765)
- B. (298)(750)(40)/(50)(765)
- C. (298)(765)(50)/(750)(40)
- D. (40)(750)/(298)(50)(765)
Explanation: PV=nRTAccording to the ideal gas equation: PV = nRT. P1V1/T1=P2V2/T2 OrT2=P2V2T1/ P1V1 So T2 Should be solved as follows T2…
Correct answer: (298)(765)(50)/(750)(40)