The density of an unknown gas is 0.731 g/L at 20°C and 1.035 atm.What is the molar mass of the gas?

Question

Quizplus · Accepted Answer

The molar mass of the gas can be calculated using the ideal gas law rearranged to solve for molar mass (M): $M = \frac{dRT}{P}$, where $d$ is the density of the gas (0.731 g/L), $R$ is the ideal gas constant (0.0821 L·atm/(K·mol)), $T$ is the temperature in Kelvin (293K, since 20°C = 293K), and $P$ is the pressure (1.035 atm). Plugging in the values: $M = \frac{(0.731 g/L) \times (0.0821 L·atm/(K·mol)) \times 293K}{1.035 atm}$ gives a molar mass close to 17.0 g/mol.

The Density of an Unknown Gas Is 0