Stoichiometry Problem

Question

C2H4 + O2 → CO2 + H2O

-If you start with 45 grams of ethylene (C2H4), how many grams of carbon dioxide should be produced?
-Theoretically, how many liters of carbon dioxide will you produce if 55.3 grams of water are yielded?
-How many liter of carbon dioxide will be produced if 7.78 moles of oxygen are consumed?

Answer 1

First thing you should do is balance your equation:

 

C2H4 + O2 -> CO2 + H2O

C2H4 + O2 -> 2CO2 + 2H2O

C2H4 + 3O2 -> 2CO2 + 2H2O

 

Now, convert the 45 grams of ethylene to moles:

45g/(28g/mol) = 1.607 mol

 

Convert to moles of CO2:

2mol CO2 = 1mol Ethylene

3.214 mol CO2 produced

 

Covert back to grams:

3.214mol*(44g/mol) = 141.46 g CO2 produced

 

Convert 55.3 grams of water to moles:

55.3g/(18g/mol) = 3.072 mol

 

Convert to moles of CO2:

2 moles of CO2 = 2 moles of H2O

3.072 mol CO2 produced

 

Convert to grams:

135.168 g CO2 produced

 

Convert moles of O2 to moles of CO2

2 moles CO2 = 3 moles of O2

5.1867 mol CO2 produced

 

Assuming CO2 is an ideal gas at STP

Volume of CO2 = 22.4*moles of CO2

116.18 L CO2 produced