Question on Stoichiometry

0.25 moles of sulphur was burnt to form SO₂ which is oxidised by Cl₂ water. The solution is treated with BaCl₂ solution. How many moles of BaSO₄ will precipitate?

Answer:

All the moles of sulphur taken initially will be present in the BaSO₄ precipitate. As one mole of BaSO₄ contains one mole of sulphur in it and 0.25 moles of sulphur (taken initially) will be present in it, 0.25 moles of BaSO₄ will precipitate.