Chemical kinetics
11.0 Uses the principles of chemical kinetics in determining the rate of a chemical reaction and in controlling the rate of reactions
11.1 Introduces reaction rate and determines the factors affecting the rate of chemical reactions
Generalizes a chemical reaction as aA + bB →cC + dD
Provides examples for chemical reactions taking place at various rates and compares the rates of different reactions.
States that the change in the concentration of a substance is the fundamental factor in measuring the rate of a reaction.
Defines rate of reaction as rate with respect to the change of concentration of the reactant A (ΔCA/Δt) or rate with respect to the change of concentration of the product D (ΔCD/Δt).
Expresses that in a given reaction, the rate of removal of each reactant and rate of formation of each product are not equal.
States that the rate of removal of a reactant or formation of a product depends on the stoichiometric coefficients of the respective substances.
States accordingly that the generalized rate of a reaction =(-1/a) (ΔCA/Δt) = (1/d) (ΔCD/Δt).
States that for any type of change, rate is the change of concentration per unit time.
Illustrates with examples that time taken for a given constant change can be used in rate measurements (rate α 1/t)
Expresses that properties (colour intensity, turbidity etc.) which depend on the amount of a substance or concentration can also be used to compare rates.
Provides examples for slow reactions where time can be easily measured for the determination of rates.
Identifies the factors affecting the rate of a reaction - temperature, concentration, pressure, physical nature (surface area of reactants),catalysts.
11.2 Uses molecular kinetic theory to explain the effect of factors affecting the rate of chemical reactions
Draws energy diagrams for a single step reactions .
Defines the term activation energy.
Lists the requirements essential for a reaction to occur.
States that when temperature increases kinetic energy of molecules is also increased.
Draws the simplified form of Boltzmann distribution curve for gaseous molecules at two different temperatures and compares the kinetic energy of molecules at different temperatures.
Explains the increase in rate of a reaction with temperature in terms of the increase of kinetic energy of molecules and thereby the number of collisions.
Explains the increase of the number of collisions per unit volume per unit time using the concept of concentration.
States that collisions having appropriate orientation is proportional to the total number of collisions.
11.3 Controls the rate of a reaction by appropriately manipulating the concentration of reactants.
Displays initial rate, instantaneous rate and average rate of a reaction using suitable graphs.
Explains how the order of the reaction with respect to a given reactant and concentration of that reactant affects the rate of the reaction.
Defines the rate law for reactions as, rate = k [A]x [B]y .
Defines the terms in the rate law.
Writes the rate law (equation) for zeroth, first and second order reactions.
Derives the units of the rate constant (coherent SI units and noncoherent SI units) for zeroth, first and second order reactions.
Interprets the overall order of a reaction.
Demonstrates graphically how the rate changes with concentration for a zero order, first order and second order reaction.
Defines and interprets half-life of a reaction.
Explains that half life of first order reactions does not depend on the initial concentration.
Provides examples for reactions of different orders.
Conducts experiments to illustrate zeroth order, first order and second order reactions.
Determines order of reactions with respect to various reactants by handling appropriately the information obtained from experiments.
Solves problems related to rate law and order of reactions.
11.4 Investigates the effect of physical nature and catalysts on reaction rate
States that when surface area of a solid reactant increases rate of reaction also increases due to the increase of number of collisions.
Describes the effect of catalyst in terms of the activation energy for the reaction.
11.5 Uses reaction mechanisms to describe the rate of chemical reactions
Distinguishes elementary reactions from multistep reactions.
Explains the relationship between the mechanism of a reaction and the order of a reaction.
Draws energy profiles.
Identifies the intermediates and transitions states of the energy diagram.
Explains the molecularity and the order of the elementary and multistep reactions.
Constructs energy profiles for reactions to explain the events that follow collisions using basic principles of energetics.
Explains the effect of concentration of iron(III) ions on the reaction rate of the reaction between Fe3+ and I-
Explains the relationship between the mechanism of a reaction and the order of a reaction.
Determines the rate determining step and reaction mechanisms using energy profiles.