Data

Volume of Sulphur dioxide = 5 liters
Molar volume at S.T.P = 22.4dm³/mole
Asked:
i. Moles of Sulphur to oxide (SO₃)
ii. Volume of Sulphur to oxide (SO₃)
The balanced chemical equation for the reaction.

2SO_2(g) + O₂ ⇋ 2SO_3(g)
2 moles: 1 mole: 2 moles

To convert 5 liters of SO₂ into mole
Mole = volume / Molar volumes
= 5 dm³ / 22.4 dm³/mole
= 0.2232142857 mole of SO₂

i/ find the moles of SO₃ formed

from equivalent moles:
2 moles of SO₂ Ξ 2 moles of SO₃
0.2232142857 mole of SO₂ Ξ ?? of SO₃

= (0.2232142857 mole × 2 mole) / 2 mole
= 0.2232142857 mole

0.223mole of Sulphur trioxide was formed.

ii/ find the volume of Sulphur trioxide (SO₃) from equivalent mole.

2 moles of SO₂ Ξ 2 moles of SO₃
0.2232142857 moles Ξ ?? of SO₃

= (0.2232142857 mole × 2 moles) / 2 moles
= 0.2232142857 moles of SO₃

convert 0.2232142857 mole into volume at S.T.P

Volume = mole × molar volume
= 0.2232142857 mole × 22.4 dm³/mole
= 5 dm³

5 liters of Sulphur trioxide was produced at S.T.P.