B. Example Calculations
1) 2SO2 (g) + O2 (g) -> 2SO3 (g) If you have 3.5 moles of O2 (g), how many moles of SO3 (g) can be formed?
3.5 mol of O2 X 2 mol SO3/1 mol O2
Answer- 7.0mol of SO3
2) LiOH + CO2 -> Li2CO3 + H2O
How many moles of Li2CO3 will be formed with 1000g of LiOH? Give percent yield.
Answer- 2LiOH + CO2 -> Li2CO3 + H2O
1000.00 g LiOH x 1 mol LiOH/23.95 g LiOH x 1 mol Li2CO3/2 mol LiOH
20.9 mole Li2CO3
10.1/20.9x100=48%
3) If you have 20.5 g of LiOH from 200 g of SO3 and we have 15.4 g of LiOH from PO4 what are the limiting and exces reagents?
Answer- Limiting: PO4
Excess: SO3
3.5 mol of O2 X 2 mol SO3/1 mol O2
Answer- 7.0mol of SO3
2) LiOH + CO2 -> Li2CO3 + H2O
How many moles of Li2CO3 will be formed with 1000g of LiOH? Give percent yield.
Answer- 2LiOH + CO2 -> Li2CO3 + H2O
1000.00 g LiOH x 1 mol LiOH/23.95 g LiOH x 1 mol Li2CO3/2 mol LiOH
20.9 mole Li2CO3
10.1/20.9x100=48%
3) If you have 20.5 g of LiOH from 200 g of SO3 and we have 15.4 g of LiOH from PO4 what are the limiting and exces reagents?
Answer- Limiting: PO4
Excess: SO3