Helppp pleasee Part A
Calculate the density of sulfur hexafluoride gas at 93.6 kPa and
23 °C. Express the density in grams per liter to three significant digits.

Part B
Calculate the molar mass of a vapor that has a density of 7.125 g/L at
11 °C and 99.1 kPa. Express the molar mass in grams per mole to three significant digits.
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considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.