Save
...
Physical Chemistry
Energetics
Hess’s Law
Save
Share
Learn
Content
Leaderboard
Share
Learn
Created by
z
Visit profile
Cards (4)
What is Hess’s law?
The total
enthalpy change
for a reaction is independent of the route taken.
What is an enthalpy cycles used for?
To calculate
enthalpies
of reaction/formation that are
difficult
to experiment
Equation for Hess’s law cycles
Δ
H
\Delta H
Δ
H
r =
∑
H
\sum_{ }^{ }H
∑
H
f of
products
-
∑
H
\sum_{ }^{ }H
∑
H
f of
reactants
Calculating enathalpy of reaction from enthalpies of combustion
Δ
H
\Delta H
Δ
H
=
∑
\sum_{ }^{ }
∑
Δ
H
\Delta H
Δ
H
c of
reactants
-
Σ
Δ
H
\Sigma\Delta H
ΣΔ
H
c of
products
