Topic 16 - Kinetics II

• Rate = change in concentration of products or reactants/time
• Quenching is the process of slowing down or stopping a reaction
• If you increase the concentration of a reactant and the initial rate stays the same, the order is 0
• If you increase the concentration of a reactant and initial rate increases by the same factor, the order is 1
• If you increase the concentration of a reactant and the initial rate increases by that factor squared, the order is 2
• The overall order of a reaction is the sum of all reactant orders
• $rate=$$k[A]^m+$$[B]^n$

  m and n being orders, [A] and [B] being concentrations of reactants
• K increases with temperature
• The higher k is, the faster the rate of reaction is
• If the number or type of ions changes over a reaction, rate can be measured using a conductivity metre
• A reason why a reactant could be order 0 is because it is not involved in the rate determining step of a reaction
• The slowest step of a reaction is the rate determining step
• Order 0 graphs are straight, order 1 and 2 graphs are curved
• Rate of reaction stays the same despite concentration falling for order 0 reactants
• The difference between order 1 and 2 graphs, is that for order 2 half life increases
• Half life is the time taken for concentration to fall by half
• During reactions, an intermediate forms that turns into the product
• Intermediates cancel out and are only present for very short periods of time as they are very reactive
• Rate of reactions for gas producing reactions can be measured by measuring the weight of the system throughout a reaction
• Arrhenius equation -

  lnK = lnA - Ea/RT
• The K in the arrhenius equation stands for rate constant
• The A in the arrhenius equation stands for pre exponential frequency facot
• The e in the arrhenius equation stands for euler's number
• The e in the arrhenius equation stands for euler's number
• The Ea in the arrhenius equation stands for activation energy
• The R in the arrhenius equation stands for gas constant
• The T in the arrhenius equation stands for temperature in kelvins
• The T in the arrhenius equation stands for temperature in kelvins
• lnK is the y axis
• 1/T is the x axis
• -Ea/R is the gradient
• lnA is the y intercept
• Particles can only react once they have reached transition state
• Transition state has no significant time period and is essentially the point when particles collide
• Transition state has no significant time period and is essentially the point when particles collide
• Transition state occurs at the top of the energy curve so it has an energy maximum
• Transition state occurs at the top of the energy curve so it has an energy maximum
• Catalysis is the process in which the rate of a chemical reaction is increased by adding a catalyst
• Catalysis is the process in which the rate of a chemical reaction is increased by adding a catalyst
• A catalyst increases the rate of reaction by providing the reactants an alternate reaction pathway lower in activation energy