Thermochemistry Flashcards
1
Q
What is Enthalpy?
A
The measurement of energy in a thermodynamic system.
2
Q
What are the two types of energies within chemical species?
A
Potential Energy - energy associated with chemical bonds present or CE
Kinetic Energy - energy associated with atomic and molecular movement
H = Ep + Ek
3
Q
Changes in Enthalpy are given by…
A
Hp - Hr = changes in enthalpy
4
Q
What happens in an Exothermic reaction?
A
Energy is released into the environment therefore products have lower energy than reactants.
Change in enthalpy = negative
5
Q
What happens in an endothermic reaction?
A
Energy is absorbed from the environment therefore products have higher energy than reactants
Change in enthalpy = positve
6
Q
What 3 things must occur for a reaction to start?
A
- Particles A+B must collide
- Collision must overcome Activation Energy Barrier
- Collision must occur at the correct orientation
