Answer :
Final answer:
The unknown gas in Container 3 has a molar mass of 32 g/mol, suggesting it is oxygen (O₂). Since Container 1 and Container 2 have the same pressure, they should contain equal masses of Helium and Neon, respectively. So, the correct option is D. 8.00 g; 8.00 g.
Explanation:
The student's question pertains to the determination of the masses of gases present in containers under a given pressure but with the mass of the gas being unknown for one of them. In this problem, there are four containers, each with different gases (Helium, Neon, an unknown gas, and Sulfur Dioxide) having the pressures and masses mentioned.
For Container 3, we need to identify the molar mass of the unknown gas, which would help us determine its identity. Using the ideal gas law (PV=nRT), and assuming the conditions of temperature and volume are the same as Container 4, we can compare the masses of the gases to their molar masses. The answer must allow the unknown gas to have a molar mass that, when the mass is divided by it, results in the same number of moles as found in Container 4, since it has a slightly lower pressure but virtually the same mass.
Using calculations, we can find that the unknown gas in Container 3 has a molar mass of approximately 32 g/mol. Therefore, the gas is likely to be oxygen (O₂), which has a molar mass of 32 g/mol. Now, Container 1 should have the same mass of helium as Container 2 has of neon since they are both under the same pressure. Therefore, we are looking for equal masses of the gases in Container 1 and 2, which means the correct option is D. 8.00 g; 8.00 g.