Question

When lead (II) sulfide is burned in air, lead (II) oxide and sulfur dioxide are produced. If 20. L of sulfur dioxide are produced, how many liters of oxygen gas were reacted at STP?

Answer 1

2PbS(s) + 3O₂(g) ==> 2PbO(s) + 2SO₂(g)

Mass of $SO_2= 2.63×20=52.6$

Moles of $SO_2 =\frac{52.6}{64}=0.822 moles$

Moles of oxygen =$\frac{0.822×3}{2}=1.233moles$

Mass of $O_2= 1.233×16=19.728g$

Volume in liters $= 19.728×1.4728=29.06L$