5.2 Hess's law Flashcards
1
Q
Describe energy cycle
A
Clockwise: combined and burned
Anti-clockwise: burned seprately
2
Q
State Hess’s law
A
Hess’s law: enthalpy of the reaction is independent of the route that is taken (direct vs indirect route)
3
Q
What is the importance of Hess’s law
A
4
Q
Direct vs indirect route of reaction
A
Direct = delta H 3
Indirect = delta H 1 + delta H 2
5
Q
Standard enthalpy change conditions
A
298K, 1x105 Pa
6
Q
Define standard enthalpy of formation
A
Standard enthalpy of formation: enthalpy change that occurs when 1 mol of substance is formed form its elements in their standard states
7
Q
Define standard enthalpy change
A
Standard enthalpy change: enthalpy change for a particular reaction
