COMEDK20269 May 2026Evening ShiftPhysicsKinetic Theory of GasesActual
A vessel of volume 27 10^4 cc, contains a mixture of Hydrogen (molar mass = 2 g mol⁻¹ ) and oxygen (molar mass = 32 g mol⁻¹ ) gas at standard temperature and pressure. If the mass of hydrogen is 16 g, find the mass of oxygen gas contained in the vessel.
Options
- A72 g
- B129.7 g
- C64 g
- D160 g
Correct answer
B. 129.7 g
Step-by-step solution
Volume of the vessel, V = 27 10^4 cc = 270 L At STP, the volume of 1 mole of an ideal gas is 22.4 L. Total number of moles in the mixture, n = 270 22.4 12.054 Number of moles of hydrogen, n_ H₂ = 16 2 = 8 Number of moles of oxygen, n_ O₂ = n - n_ H₂ = 12.054 - 8 = 4.054 Mass of oxygen, m_ O₂ = n_ O₂ 32 = 4.054 32 129.7 g Answer: 129.7 g