Balance the equation below and use it to answer the following questions. C4H10 + O2 ==> CO2 + H2O

1-How many moles of oxygen are needed to react with 86.2 g of butane?
2-If 5.9 moles of butane is reacted, what mass of water is produced?
3-If 49.3 g of carbon dioxide is produced, what mass of water is also produced?
4-How many moles of oxygen gas are needed to produce 0.365 moles of carbon dioxide?

2C4H10 + 13O2-----> 8CO2 + 10H2O
1) 86.2 g C4H10 / (58.12 g/mol) = 1.48 mol C4H10
1.48 mol C4H10 * (13 mol O2 / 2 mol C4H10) = 9.64 mol O2

2)5.9 mol C4H10 * (10 mol H2O / 2 mol C4H10) = 29.5 mol H2O
29.5 mol H2O * (18.015 g/mol) = 531 g H2O

3)49.3 g CO2 / (44.01 g/mol) = 1.12 mol CO2
1.12 mol CO2 * (10 mol H2O / 8 mol CO2) = 1.40 mol H2O
1.40 mol H2O * (18.015 g/mol) = 25.2 g H2O

4) .365 mol CO2 * (13 mol O2/ 8 mol CO2) = .593 mol O2