The combustion of octane is a common reaction in automobile engines.
1) 2 C8H18 (l)
+ 25 O2 (g) à 16 CO2 (g)
+ 18 H2O (g) ΔH1 =
-250 kJ/mole
2) 18 H2O
(l) à 18 H2O (g) ΔH2 =
88 kJ/mole
Net Reaction:
3) 2 C8H18 (l)
+ 25 O2 (g) à 16 CO2 (g)
+ 18 H2O (l) ΔH3 =
?
Given ΔH1 and
ΔH2, what is ΔH3 for the net reaction above?
A. 163 kJ/mole
B. -163 kJ/mole
C. 333 kJ/mole
D. -333 kJ/mole