Hess Cycles Flashcards
1
Q
What is Hess’ law?
A
If a reaction can take place by more than 1 route, provided the initial and final conditions are the same, the total enthalpy change for each route is the same
2
Q
How is a combustion Hess cycle drawn?
A
Reactants —————————> products
. /
. /
>. combustion products. <
3
Q
How do you calculate ΔrH?
A
ΔrH = ΔH1 - ΔH2
4
Q
How do you draw a formation Hess cycle?
A
Reactants —— —> products
. /
. /
>. elements <
5
Q
What is the enthalpy change of elements?
A
Always zero
