Question

Consider the following hydrocarbon fuels:
a. CH4 b. C2H4 c.C2H6

Rank them in terms of heat released:
(a) per mole
(b) per gram

(Assume that H2O forms and that combustion is complete)

Answer 1

-first step is to write out the decay reactions!
-Then use Hesses law to find their heat of combustion, which should come out as
Joules per mole

- Then just use unit conversion to get joules per gram

Answer 2

https://en.wikipedia.org/wiki/Hess%27s_law

first equation when scrolling down the page