Consider the combustion of propane gas, 
C3H8(g) + 5O2(g) 3CO2(g) + 4H2O(l) Ho = -2,220 kJ/mol 

Propane is often used for gas grills and is typically purchased by filling a propane tank with 20 pounds of propane. What is the enthalpy change when 14 pound of propane is burned? Use the conversion 1 lb = 454 g and express your answer in scientific notation. For example use 2.3e-5 to indicate a number such as 2.3 x 10-5.
1 kJ 
What is the enthalpy change for 
9 CO2(g) + 12 H2O(l) 3 C3H8(g) + 15 O2(g) 

Hint, compare this equation to the combustion equation for propane. 
2kJ