What is the volume of sulfur oxide (6) weighing 500 g?

Given:
m (SO3) = 500 g
Vm = 22.4 l / mol

To find:
V (SO3) -?

Decision:
1) Using the periodic system of D.I.Mendeleev, calculate the molar mass of SO3, which will be numerically equal to the relative molecular mass:
M (SO3) = Mr (SO3) = Ar (S) + Ar (O) * 3 = 32 + 16 * 3 = 80 g / mol;
2) Calculate the amount of substance SO3:
n (SO3) = m (SO3) / M (SO3) = 500/80 = 6.25 mol;
3) Calculate the volume of SO3 (under normal conditions):
V (SO3) = n (SO3) * Vm = 6.25 * 22.4 = 140 liters.

Answer: The volume of SO3 is 140 liters.