a Calculate the number of oxygon molecules and the number of

a -Calculate the number of oxygon molecules and the number of oxygon atoms in 31.1 g of oxygon

(enter the answer in scientific notation)

b- calculate the mass of 9.05 * 10^14 SO3

c- repeat the same question ( a & b) but the number of oxygon atoms in 42.9 (a) and calculate the mass of 9.19 *10^14 (b)

a) Oxygen Molecules = 31.1 / 32 * Na = 5.854 * 10^23 molecules

Oxygen Atoms = 2*5.854 * 10^23 = 1.17 * 10^24 atoms

b) What is the unit of 9.05 * 10^14?

c) Please mention units in this case too.