verify that suggested reaction mechanism is consistent w/ observed kinetics
g
predict order of rxn from given reaction mechanism
v
calculating initial rate using conc data
v
half-life of 1st order reaction is independent of conc
r
use half-life of 1st order reaction in calculation
r
calculate rate constant using initial rates method
d
devise suitable experiment technique for studying rate of reaction from given info
g
explain in terms of freq of collisions, effect of conc changes on rate of rxn
r
what is meant by activation energy wrt Boltzmann distribution
f
explain in terms of Boltzmann distribution & collision freq, effect of temp change on rate constant, hence on rate of rxn
r
explain that when catalyst present reaction has diff reaction mechanism, ie one of lower Ea giving larger rate constant
f
interpret catalytic effect on rate constant in terms of boltzmann distribution
c
outline diff modes of action of homogenous, heterozygous catalysis including;
haber process
catalytic removal of oxides of nitrogen in exhaust gases from car engines
catalytic role of atmospheric oxides of nitrogen in oxidation of atmospheric sulfur dioxide
catalytic role of fe2+ in I-/S2O82- reaction
d
describe enzymes as biological catalysts which have specific activity
d
explain r/s b/w [substrate] & rate of enzyme-catalysed reaction in biochemical systems
d
define rate of reaction
change in conc of reactant/product per unit time
define order of reaction
power to which conc of reactant is raised to in rate equation
define rate constant
k, constant of proportionality in rate equation
define half-life of reaction
t1/2, time taken for [reactant] to decrease to 1/2 of initial value
define rate-determining step
slowest step in reaction mechanism, rate eqn obtained from rds
define activation energy
Ea, minimum amount of energy required for effective collision resulting in reaction
define rate equation
mathematical equation that defines rate as the product of rate constant & conc. of reactants raised to appropriate powers
how to deduce order of reaction by initial rates method
compare initial rates of 2 or more experiments for known initial concentrations by:
1. inspection method
- e.g. compare expt 1 & 2 where [A], [B] constant, doubling [C] doubles rate.
rate is proportional [C]
2. calculation
- rate 2/rate 1 = rate eqn 2/rate eqn 1 to find unknown
how to find unit of rate constant, k
unit of k = unit of rate/(unit of conc)n; n=overall order
how to determine order of reaction from conc-time graph?
zero order reaction - straight line passing through origin w/ +ve gradient
first order reaction - consistent t1/2 obtained, can start @ initial conc
second order reaction - inconsistent t1/2