Reaction Pathways Flashcards
(11 cards)
How is the potential energy diagram used?
A potential energy diagram can be used to show the energy pathway for a reaction.
What is enthalpy change?
The enthalpy change (H) is the energy difference between the products and the reactants.
How is the enthalpy change measured for the forward reaction?
The enthalpy change is measured from R to P.
How is the enthalpy change measured for the backward reaction?
The enthalpy change is measured from P to R.
What is the activation energy?
The activation energy (Ea) is the minimum energy required by colliding molecules to form an activated complex.
How is the activation energy measured for the forward reaction?
Activation energy is measured from R to top of the hill for the forward reaction.
How is the activation energy measured for the backward reaction?
Activation energy is measured from P to bottom of the hill for the reverse reaction.
What is an activated complex?
The activated complex is an unstable arrangement of atoms formed at the maximum of the potential energy barrier, during a reaction.
What role do catalysts have in a reaction pathway?
A catalyst provides an alternate reaction pathway with a lowering of the activation energy. Adding a catalyst has no effect on the enthalpy change (H).
Hess’s Law
Hess Law states that the enthalpy change of a chemical reaction is independent of the route taken.
