Question

Calculate the molar mass of a gas if an 8.06×10(to the power of -2) gram sample of it occupies .0650 L at 547°C and 70.5 kPa​

Answer 1

Answer:

                     M.Mass = 120 g/mol

Explanation:

Data Given:

                  Volume = V = 0.0650 L

                  Temperature = T = 547 °C = 820.15 K

                  Pressure = P = 70.5 kPa = 0.695 atm

                  Gas Constant = R = 0.082057 L.atm.mol⁻¹.K⁻¹

Formula Used:

                        Assuming that the gas is ideally then according to ideal gas equation,

                                   P V = n R T

Solving for n,

                                   n = P V / R T

Putting Values,

    n = (0.695 atm × 0.0650 L) ÷ (0.082057 L.atm.mol⁻¹.K⁻¹ × 820.15 K)

    n = 6.71 × 10⁻⁴ moles

Now, Knowing that,

                                  Moles  =  Mass / M.Mass

Or,

                                  M.Mass = Mass / Moles

Putting values,

                                  M.Mass = 8.06 × 10⁻² g / 6.71 × 10⁻⁴ mol

                                  M.Mass = 120 g/mol