Final answer:
To determine the unknown gas, calculate the number of moles using the ideal gas law and compare it to the molar masses of the given gases. Nitrogen (N₂) is most likely the unknown gas.
Step-by-step explanation:
To determine the unknown gas, we can compare the given pressure and temperature with the known properties of different gases. The ideal gas law equation (PV = nRT) can be used to calculate the number of moles of gas present.
Using the ideal gas law, we can calculate the number of moles of the unknown gas as n = PV/RT. Since we are given the pressure, volume, and temperature, we can substitute those values into the equation.
Once we have the number of moles, we can compare it to the molar masses of the gases given in the answer choices. The gas with a molar mass closest to the calculated value is most likely to be the unknown gas.
In this case, we calculate that the unknown gas has a molar mass of approximately 28 g/mol. Among the answer choices, Nitrogen (N₂) has the closest molar mass to this calculated value. Therefore, Nitrogen (N₂) is the most likely to be the unknown gas.