Hess' law is used to determine reaction enthalpy change indirectly (using an alternative route of reaction)

Hess' law can be calculated using bond enthalpies or expermental data to determine ΔH1 and ΔH2

1

What is the first step to using Hess' Law?

2

Calculate ΔHr for the reaction shown in the picture.

3

Calculate ΔHr for the reaction shown in the diagram.

4

Using the Hess cycle given, what is the standard enthalpy of reaction for CaCO₃ → CO₂ + CaO?

5

What is Hess' Law?