Hess’ Law & Enthalpy Cycles Flashcards
1
Q
What does Hess’ law state?
A
The enthalpy change of a reaction is the same, regardless of the route taken, under standard conditions.
2
Q
What is an enthalpy cycle?
A
Diagram showing alternative routes between reactants and products which allows the indirect determination of an enthalpy change from other known enthalpy changes using Hess’ law.
3
Q
How do you calculate the enthalpy change of combustion using an enthalpy cycle?
A
(Sum of enthalpies of reactants) - (sum of enthalpies of products)
4
Q
How do you calculate the enthalpy change of formation using an enthalpy cycle?
A
(Sum of enthalpies of products) - ( sum of enthalpies of reactants)
