Chemistry
posted by Natalie .
Can someone PLEASE help me with this???? I am soooo confused with this problem!!!
Combustion reactions involve reacting When compounds containing carbon and hydrogen are combusted, carbon dioxide and water are the products. Using the enthalpies of combustion for C4H4 (2341 kJ/mol), C4H8 (2766 kJ/mol) and H2 (286 kJ/mol), calculate delta H for the reaction
C4H4(g) + 2H2(g) > C4H8(g)

(1)C4H4 + 5 O2 ==> 4CO2 + 2H2O 2341 kJ/mol
(2)C4H8 + 6 O2 ==> 4CO2 + 4H2O 2766 kJ/mol
(3)H2 + 1/2 O2 ==> H2O 286 kJ/mol
Add equation 1, to reversed equation 2, to twice equation 3 and you should get the equation you want of C4H4 + 2H2 ==> C4H8.
Remember to change the sign of equations that are reversed and to multiply the kJ/mol of equations that are multiplied. Post your work if you get stuck. 
Thanks SO much for the help!:)