Answer:
B.) 0.316
Explanation:
To find the moles, you need to multiply the given value by the molar mass. The molar mass is made up of each element's atomic mass times their quantities. It is important to arrange the conversion in a way that allows for the cancellation of units.
Atomic Mass (S): 32.065 g/mol
Atomic Mass (O): 15.998 g/mol
Molar Mass (SO₃): 32.065 g/mol + 3(15.998 g/mol)
Molar Mass (SO₃): 80.059 g/mol
25.3 grams SO₃ 1 mole
------------------------- x ------------------------- = 0.316 moles SO₃
80.059 grams
