What is the molar mass of compound (freon) 4.38 x 10^3 kPa at 24degrees (please read details)?

The molar mass of a compound is its weight per one mole of compound.

The weight is given. You need to find the number of moles which can be calculated using the Ideal Gas Law:  PV = nRT.

n = PV/RT

Since the gas constant's unit is L-atm/K-mol, you need to convert the pressure to atm and the temperature to absolute temperature.

Then, simply divide the weight of the compound by the number of moles of the compound to determine its molar mass.

It looks like the variables can fit in the ideal gas equation of PV = nRT
P = pressure, V= volume , n is gas moles, R is constant, and T is temperature

We are solving for n, so n = PV/ RT
To find kelvin, add 273 K (0 C) to 24 C

n = (4380 kPa)(10.9L) / (8.314 L kPa mol^-1 K^-1)(297 K)
Note that kPa, L and K will cancel out, leaving you with just moles

n = 47742 kPa L / 2469.258 L kPa mol^-1) = 19.33 moles of Freon-23

Since 1.35kg in molar mass would be 1,350g,
We divide 1,350 over 19.33 to get grams per mole

1,350g / 19.33mol = 69.8 g/mol, the molar mass of Freon-23