Question

What is the molar mass of a gas if 0.0494 g of the gas occupies a volume of 0.100 L at a temperature 26 °C and a pressure of 307 torr?

a) 28.58 g/mol
b) 45.72 g/mol
c) 62.94 g/mol
d) 78.23 g/mol

Answer 1

The molar mass of a gas is calculated using the ideal gas equation PV = nRT, along with conversions for pressure, volume, and temperature into consistent units. After solving for the number of moles, the molar mass is found by dividing the mass of the gas by the number of moles.

Step-by-step explanation:

The molar mass of a gas can be calculated using the ideal gas equation: PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant (0.0821 L·atm/mol·K), and T is the temperature in Kelvin. To calculate the molar mass (M), we first need to convert all measurements to appropriate units: pressure in atm (1 atm = 760 torr), volume in liters (0.100 L), and temperature to Kelvin (26°C + 273.15 = 299.15 K).

We then rearrange the ideal gas equation to solve for the number of moles (n = PV/RT), and then use this value to find the molar mass (M = mass of gas in grams / n). After performing the calculations with the provided data (0.0494 g, 307 torr, and 0.100 L), we find the molar mass of the gas.