Final answer:
The total pressure of the N2, O2, and He gas mixture is 471 torr. To find the mass of each gas in the 1.50-L volume at 25.0 °C, apply the ideal gas law to determine the moles of each gas, and then multiply by its respective molar mass.
Step-by-step explanation:
The total pressure of the gas mixture containing N2, O2, and He can be calculated using Dalton's Law of Partial Pressures, which states that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the individual gases. In this case, we sum up the given partial pressures to find the total pressure:
Total pressure = 211 torr (N2) + 101 torr (O2) + 159 torr (He) = 471 torr.
To calculate the mass of each gas in the 1.50-L sample at 25.0 °C, we use the ideal gas law, which can be rearranged in terms of n (number of moles): PV = nRT, where P is the partial pressure of the gas, V is the volume, R is the gas constant, and T is the temperature in Kelvin. To find the mass, we first calculate the number of moles and then use the molar mass (M) of each gas: Mass = n × M.