Question

MEDAL, FAN, AND TESTIMONIAL

In the manufacturing process of sulfuric acid, sulfur dioxide is reacted with oxygen to produce sulfur trioxide. Using the equation, 2SO2 (g) + O2 -> 2SO3 (g), if 128 g of sulfur dioxide is given the opportunity to react with an excess of oxygen, but only produces 144 g of sulfur trioxide, what is the percent yield of this reaction?

29.24%

58.48%

90.0%

100.0%

Answer 1

Molar mass of SO2 = 64g
So 2 moles of SO2 is being used.
2 moles of SO2 used => 2 moles of SO3 produced.
Mass of SO3 produced = 144g
Molar mass of SO3 = 80g
=> No of moles of SO3 = 144/80 = 1.8

% yield = 1.8*100/2 = 90%

Answer 2

90%