Question

I would really appreciate some help with this question:
Sulfur dioxide reacts with oxygen to produce sulfur trioxide:

2SO2(g) + O2(g) → 2SO3(g)

What mass of oxygen, in grams, would react completely with 1.28 g of sulfur dioxide?

Relative atomic masses (Ar): sulfur = 32, oxygen = 16

Answer 1

2 moles of sulfur dioxide : one mole of oxygen
Moles= mass/Mr
n= 1.28/(32+32)= 0.02 moles
0.02/2= 0.01 moles of oxygen
0.01 x 64 = 0.64g of oxygen