+# Rates and Equilibria
+
+## Energy profile diagrams
+
+$$E_A = E_{\text{max}} - E_{\text{initial}}$$
+
+- Energy always needed to initiate reaction (break bonds of reactants)
+- Reactant particles must collide at correct angle, energy etc
+- Most collisions are not fruitful
+
+![](graphics/endothermic-profile.png)
+![](graphics/exothermic-profile.png)
+
+**Ways to increase rate of reaction:**
+
+1. Increase surface area
+2. Increase concentration/pressure
+3. Increase temperature
+
+## Kinetic energy
+
+Temperature - measure of _avg_ kinetic energy of particles. Over time each particle will eventually have enough energy to overcome $E_A$.
+Note same distribution indicates same temperature.
+![](graphics/ke-temperature.png)
+
+## Catalysts
+
+- alternate reaction pathway, with lower $E_A$
+- increased rate of reaction
+- involved in reaction but regenerated at end
+
+**Homogenous** catalyst: same state as reactants and products, e.g. Cl* radicals.
+**Hetrogenous** catalyst: different state, easily separated. Preferred for manufacturing.
+![](graphics/catalyst-graph.png)