Answer :
Final answer:
The molar mass of the gas is calculated using the ideal gas law rearranged to solve for molar mass (M = mRT / PV). The given values for the mass of the gas, temperature, pressure, and volume are substituted in the formula, yielding a molar mass of approximately 9.79 g/mol (option a).
Explanation:
To calculate the molar mass of the gas, we can use the ideal gas law (PV = nRT) which, when rearranged to solve for molar mass (M), becomes M = mRT / PV, where:
- m is the mass of the gas (3.15 g),
- R is the ideal gas constant (0.0821 L.atm/K.mol)
- ,
- T is temperature in degrees Kelvin (20 + 273 = 293 K),
- P is the Pressure of the gas (785 mmHg, to convert to atm, we divide by 760, to get approximately 1.03 atm),
- V is the volume of the gas (750 ml, which is 0.75 L)
Now, plug in these values to get M = (3.15 g * 0.0821 L.atm/K.mol * 293 K) / (1.03 atm * 0.75 L) = approximately 9.79 g/mol. Therefore, the answer is a) 9.79 g/mol
Learn more about Molar Mass here:
https://brainly.com/question/12127540
#SPJ11