I'm stuck with part d of this question.
The equation for the formation of pentane is 5C + 6H2 -> C5H12
a. Write the products if they were burnt completely in oxygen - CO2 and H2O
b. Draw arrows to show the equations for the enthalpy change of combustion of carbon and hydrogen and of pentane - I got the arrows going down to CO2 and H2O
c. Use the standard enthalpy change of combustion data shown to calculate the standard enthalpy change of formation of pentane - this is what I got stuck on
The enthalpy change of combustion data is:
Pentane -3509
Hydrogen -286
Carbon -394
Please help!