1# Rates and Equilibria 2 3## Energy profile diagrams 4 5$$E_A = E_{\text{max}} - E_{\text{initial}}$$ 6 7- Energy always needed to initiate reaction (break bonds of reactants) 8- Reactant particles must collide at correct angle, energy etc 9- Most collisions are not fruitful 10 11 12 13 14**Ways to increase rate of reaction:** 15 161. Increase surface area 172. Increase concentration/pressure 183. Increase temperature 19 20## Kinetic energy 21 22Temperature - measure of _avg_ kinetic energy of particles. Over time each particle will eventually have enough energy to overcome $E_A$. 23Note same distribution indicates same temperature. 24 25 26## Catalysts 27 28- alternate reaction pathway, with lower $E_A$ 29- increased rate of reaction 30- involved in reaction but regenerated at end 31 32**Homogenous** catalyst: same state as reactants and products, e.g. Cl* radicals. 33**Hetrogenous** catalyst: different state, easily separated. Preferred for manufacturing. 34 35 36Many catalysts involve transition elements. 37Haber process (ammonia producition) - enzymes are catalysts for one reaction each. Adsorption (bonding on surface) forms ammonia \ce{NH3} 38 39## Equilibrium systems 40 41**Equilibrium** - the stage at which quantities of reactants and products remain unchanged 42Reaction graphs - exponential/logarithmic curves for reaction rates with time (simultaneous curves forward/back)