Answer:
The molar mass of a gas can be calculated using the ideal gas equation PV = nRT. At STP, the pressure is 1 atm, the volume is 22.4 L, and the temperature is 273 K.
The number of moles (n) of the gas can be calculated as n = PV/RT = (1 atm * 22.4 L) / (0.08206 L*atm/(mol*K) * 273 K) = 1.00 mol.
The mass of the gas can be calculated as mass = density * volume = 5.45 g/L * 22.4 L = 122 g.
The molar mass (M) of the gas can be calculated as M = mass / n = 122 g / 1.00 mol = 122 g/mol.
Therefore, the molar mass of the gas is 122 g/mol.
Step-by-step explanation: