Question

2 S(s) + 3 O2(g) -----> 2 SO3(s)

How many moles of  S are required to react completely with 1.00 mole of O2?

.....mol

How many moles of  SO3 are produced from the complete reaction of 1.00 mole of O2?

........mol

How many moles of O2 are required to produce 0.80 moles of SO3?

......mol

Answer 1

1. 2moles of S is required to react completely with 3moles of O2

Hence, (2x1)/3 moles of S is required to react completely with 1mol of O2

= 0.67mol

2. 3mol of O2 --> 2mol of SO3

1mol of O2 --> (1x2)/3 mol of SO3

= 0.67mol

3. 3moles of O2 --> 2moles of SO3

x moles of O2 --> 0.80 mol of SO3

x = (3x0.80)/2 = 1.2moles

Hence, 1.2 moles of O2 is required to produce 0.80mol of SO3