Enthalpy Changes Flashcards
What is an enthalpy change?
A change in energy
What symbol represents an enthalpy change?
ΔH
What does the ⦵ in ΔH⦵ mean?
The substances were in standard states and the measurements were taken under standard conditions
What are standard conditions?
100kPa pressure and a stated temperature
What is bond enthalpy?
The energy required to break a bond
How do you calculate the enthalpy change of a reaction?
total energy absorbed - total energy released
What is the standard enthalpy of formation?
ΔfH⦵ is the enthalpy change when 1 mole of a compound is formed from its elements in their standard states under standard conditions
What is the standard enthalpy of combustion?
ΔcH⦵ is the enthalpy change when 1 mole of a substance is completely burned in oxygen under standard conditions